# How long would an eco-drive watch last?



## kaywalker (Apr 19, 2010)

Specifically the Nighthaw. I do realize the battery may need to be replaced in 10 years. What I'm asking is if I was to change the solar battery if it died, how long the watch would last. Is there any chance it would last as long as a mechanical would?


----------



## lvt (Sep 15, 2009)

kaywalker said:


> Specifically the Nighthaw. I do realize the battery may need to be replaced in 10 years. What I'm asking is if I was to change the solar battery if it died, how long the watch would last. Is there any chance it would last as long as a mechanical would?


Quartz movements usually last very long, my first "nice" watch was a quartz chronograph given to me 15 years ago and it still run strong, your love for the watch may only last a couple of years.


----------



## narcosynthesis (Dec 28, 2009)

Citizen are quoting 80% battery life in 20 years time on the current eco-drive models.


----------



## robo21 (May 26, 2011)

Furthermore, in my pre-sales interrogation of COA personnel, I was told that the battery on the Eco-Drive is covered for the life of the watch so long as the watch has only been serviced by authorized service centers and it was purchased from an authorized dealer.


----------



## South Pender (Jul 2, 2008)

If you are asking how long a watch rechargeable battery (recharged by a solar cell) will last before needing replacement, there is no clear answer at this time. Solar-powered rechargeable batteries have not been used in watches for long enough for us to know their average, or typical, lifespan (even though they've been around for more than 15 years); there's just insufficient empirical data on this issue at hand. We definitely need to disregard the marketing bumf like "you will never need to replace the battery." 

There are a number of factors involved. One important factor is whether the battery is subjected to a number of "full recharges," such as when it runs down completely (or nearly completely) and has to be recharged a long way back to full charge. The rechargeable battery will take only so many of these before giving up. The standard recommendation from the watchmakers is to try to keep the battery "topped up"--that is, never let it go down too far, but instead keep the watch exposed to light all the time (or nearly all the time). Another factor might be the quality/efficiency of the solar cell/battery combination, with the different watch brands perhaps differing in this regard. Other factors might include the variations in temperature the watch is exposed to and impacts.

Some time ago, there was a thread on this issue, and the impression I got from the discussion was that we might think in terms of 12-15 years for the life of a solar rechargeable battery, although, as noted above, this was really not much more than speculation, and is dependent on the factors mentioned above. Frankly, I'd be surprised to find, in time, that, on average, they last 20 years. There have been reports of them dying in 3-5 years, but we don't know all the circumstances surrounding these cases.

As for the lifespan of a solar-powered-battery watch, once the battery and solar cell have been replaced, I can't see why you wouldn't get the same number of years as you got on the original solar cell/battery. So, these two elements can certainly be replaced, and the time between replacements would be (we assume) far greater than that for regular batteries. If the latter part of your question is how long will a quartz module live for (as you replace the power supply along the way), that's another good question to which we have no hard-and-fast answer. Even though quartz watches have been around for more than 40 years now, we seem to lack good empirical data on typical or average lifespans. There have been lots of reports of early (say early 1970s) watches still running, although there have also been lots of reports of much shorter lifespans. My local watchmaker (a German artisan who much prefers mechanical watches) told me once that it has been his observation that often the quartz modules just die somewhere around 25 years. This is not hard to understand if we remember what the workings of a quartz watch consist of. Integrated circuits could become corroded or give way over a long time. Solderings could give out. One would have to believe that, to a great extent, the movement's lifespan is related to the quality of the watch and, perhaps, the amount of handwork applied to the movement. One good example of this might be the Seiko 9F thermocompensated quartz movements. Seiko openly claims that these can go 50 years between full servicings (battery changes, of course, have to be made). The vulnerable parts of these movements are in vacuum-sealed housings.

So, I guess, the answer to your questions is "it all depends." ;-)


----------



## robo21 (May 26, 2011)

Agree as to full discharge/recharge cycles diminishing lifespan of rechargeable battery. But in my mind,* I* will *never* have to replace a battery in my Eco Drive watch. Citizen has given me their assurance that the battery is covered for the life of the watch. COA may have to replace the battery but not me. So it's *not* marketing hype. They say "Never needs a battery" and I choose to take them at their word.


----------



## South Pender (Jul 2, 2008)

robo21 said:


> Agree as to full discharge/recharge cycles diminishing lifespan of rechargeable battery. But in my mind,* I* will *never* have to replace a battery in my Eco Drive watch. Citizen has given me their assurance that the battery is covered for the life of the watch. COA may have to replace the battery but not me. So it's *not* marketing hype. They say "Never needs a battery" and I choose to take them at their word.


If Citizen needs to replace the battery (even though they may cover this, and you will not be responsible), it would still represent a counter-example to their marketing hype, wouldn't it. I interpreted the OP as asking about the _actual _lifespan of a solar-cell/battery unit, not whether he himself would be responsible for paying for the replacement.

I think it is now the consensus among WISs that the marketing claims of the solar-charged batteries _never_ needing replacement is just nonsense, and, in my opinion anyway, deceptive advertising.


----------



## robo21 (May 26, 2011)

I will agree to disagree. For many people 10 or 15 years will represent the most life they would want or need from a watch. At 20 years the cells are projected to have 80% of their usable charge capacity. That's fine with me as I don't deep cycle the batteries on my Eco-Drives. I don't see anything deceptive about Citizen and I am very satisfied that they will fully stand behind their product 100% if a battery fails in the Eco Drive. They really have nothing to gain by lying and I don't believe they are doing so.


----------



## petew (Apr 6, 2006)

A few points....I know that folks have had batteries replaced from Citizen and they've been charged. Maybe not for the battery, but for a pressure test, new seals, movement lubrication...something....so I'm not 100% convinced that you could send an eco to COA and say ....just replace the battery and do nothing, and get a free service. They may insist on pressure testing and new seals. I'd be interested in hearing some thoughts on this.

One thing not mentioned is the lifespan of the solar cell. Those have finite lifespans as well....but...we don't know how long. I've recently noticed that at least on their Japanese site, Citizen is specifically stating that these cells will require periodic replacement.

I've had more than a couple of Eco's fail on me so I'm not as convinced as others as to there invincibility. They go in funny ways too. They stop, you do a reset, put them outside in the sun and they start right up and seem to run fine. A month later, you look at them and see that they had stopped again at some point. Mine are always kept in a bright sunny room so they get plenty of light and aren't going through drastic recycling.


----------



## South Pender (Jul 2, 2008)

robo21 said:


> I will agree to disagree. For many people 10 or 15 years will represent the most life they would want or need from a watch. At 20 years the cells are projected to have 80% of their usable charge capacity. That's fine with me as I don't deep cycle the batteries on my Eco-Drives. I don't see anything deceptive about Citizen and I am very satisfied that they will fully stand behind their product 100% if a battery fails in the Eco Drive. They really have nothing to gain by lying and I don't believe they are doing so.


I think it's safe to say that the "projection" of 80% charge left after 20 years is nothing more than speculation and is just part of the marketing bumf. Robo21, the question was not whether a person would be happy with a Citizen eco-drive watch, or whether Citizen would honor their commitment to replace the battery system once it bit the dust, but, instead, just what we might expect from this technology in terms of the lifespan of (a) the solar-cell/battery unit and (b) from the module itself. I'm happy you're happy with your Citizen watch, but, with all due respect, that's not the issue here. You state that Citizen has nothing to gain by misrepresenting the actual lifespan of a solar-rechargeable battery system, but they obviously certainly do have something to gain--*sales!* If they can convince the customer that s/he will _never_ need to have a battery change, we can reasonably assume that this will sell more watches than would a more considered and honest claim like "battery life of 15 years expected." No?


----------



## robo21 (May 26, 2011)

petew said:


> A few points....I know that folks have had batteries replaced from Citizen and they've been charged. Maybe not for the battery, but for a pressure test, new seals, movement lubrication...something....so I'm not 100% convinced that you could send an eco to COA and say ....just replace the battery and do nothing, and get a free service. They may insist on pressure testing and new seals. I'd be interested in hearing some thoughts on this.
> 
> One thing not mentioned is the lifespan of the solar cell. Those have finite lifespans as well....but...we don't know how long. I've recently noticed that at least on their Japanese site, Citizen is specifically stating that these cells will require periodic replacement.
> 
> I've had more than a couple of Eco's fail on me so I'm not as convinced as others as to there invincibility. They go in funny ways too. They stop, you do a reset, put them outside in the sun and they start right up and seem to run fine. A month later, you look at them and see that they had stopped again at some point. Mine are always kept in a bright sunny room so they get plenty of light and aren't going through drastic recycling.


I think you pretty well answered this question yourself when you said that additional work was done besides the battery replacement. Let's say for example the battery won't hold a charge and the watch movement stops. In this case the battery would be replaced at no charge. Now let's say the gaskets need replacing as well. My guess is that they would offer this service at the same time for a nominal charge, on my Skyhawk I was quoted $30. However, let's say the dead battery occurred right after a gasket change: no charge.

You may not be convinced. I am.



South Pender said:


> I think it's safe to say that the "projection" of 80% charge left after 20 years is nothing more than speculation and is just part of the marketing bumf. Robo21, the question was not whether a person would be happy with a Citizen eco-drive watch, or whether Citizen would honor their commitment to replace the battery system once it bit the dust, but, instead, just what we might expect from this technology in terms of the lifespan of (a) the solar-cell/battery unit and (b) from the module itself. I'm happy you're happy with your Citizen watch, but, with all due respect, that's not the issue here. You state that Citizen has nothing to gain by misrepresenting the actual lifespan of a solar-rechargeable battery system, but they obviously certainly do have something to gain--*sales!* If they can convince the customer that s/he will _never_ need to have a battery change, we can reasonably assume that this will sell more watches than would a more considered and honest claim like "battery life of 15 years expected." No?


All I'm saying is that for most people who care for their watch responsibly they will get much more service for much less cost with an Eco-Drive than any other movement. Citizen will back the batteries and frankly I really could not care less that you deem their marketing anything less than honest. I've had automatics, spring drives, quartz, you name it. Frankly, I just got tired of the high priced maintenance on these other movements. Never again will I fork out $450 for a cleaning/maintenance on an automatic. Even if Citizen was totally lying and I had to replace the battery in 15 or 20 years - I would be disappointed in their (hypothetical) dishonesty but I would still be way ahead financially on maintenance and battery costs compared to the other watches I've owned.

And just out of curiosity, how can you possibly say with any credibilty that "I think it's safe to say that the "projection" of 80% charge left after 20 years is nothing more than speculation and is just part of the marketing bumf?" This technology is new and hasn't been around long enough to judge that. I trust their projection a hell of a lot more than your negative assessment of their estimates. And as long as they are willing to back up their battery who cares?


----------



## South Pender (Jul 2, 2008)

robo21 said:


> And just out of curiosity, how can you possibly say with any credibilty that "I think it's safe to say that the "projection" of 80% charge left after 20 years is nothing more than speculation and is just part of the marketing bumf?" This technology is new and hasn't been around long enough to judge that. I trust their projection a hell of a lot more than your negative assessment of their estimates. And as long as they are willing to back up their battery who cares?


No need for this personal tone, robo21. Nonetheless, let me say that since there is absolutely no empirical evidence pointing to _what_ will be the case in 20 years (let alone 80% of the charge) vis-a-vis remaining charge levels, any claim is an hypothesis--or, in ordinary-language usage, speculative. It's a guess presented as though it were a fact. Citizen are certainly not alone in misrepresenting the facts about their products. If you consider the mileage claims made by almost all car manufacturers these days, you will find exactly the same thing. Vehicles that under extremely-artificial circumstances achieve a certain mileage are portrayed as yielding this mileage as a matter of course. A car advertised to give 40 mpg in a magazine or TV ad will, instead, yield about 30 mpg in a realistic driving test such as those (100-mile test drives) conducted by the Consumer's Union and reported in _Consumer Reports_. This is misleading advertising and, in my opinion, should be shut down (although I don't expect to see that). Citizen is doing much the same thing (and other watch companies are probably doing this too) by claiming that "the battery will never need replacement." Any claim about performance needs to be grounded in empirical evidence. The 80% left in 20 years has no real empirical support.

The fact that Citizen _may_ replace a defunct battery (and that too requires a large leap of faith in my opinion) in no way excuses them for misrepresentation in the first place. If they had said something like "batteries will be replaced free of charge by Citizen," this would be honest. But to anyone who respects honesty and wants truth in advertising, Citizen's corporate behavior regarding replacement is pretty much irrelevant. Many of us _do care_ about misrepresentation, regardless of corporate efforts to satisfy customers.

Finally, how do you square your views about the likely lifespan of solar-cell/battery units with petew's actual, empirical experiences? Doesn't seem like 80% left in 20 years has panned out in practice....


----------



## robo21 (May 26, 2011)

Of course South Pender, we *all* care about "misrepresentation." However, we have not established that "misrepresentations" have been made in the least. Bottom line: You have no factual basis whatsoever to make these ridiculous and completely unfounded accusations of "misrepresentation" when there is no established track record as of yet. For all we know, their estimates are right on the money. Time will tell - no pun intended. From the tone of your posts it sounds as though you have an ulterior "axe to grind." I won't theorize on your numerous and redundant usages of the word "misrepresentation" throughout your posts except to say that repeating yourself doesn't make you any more believable nor credible.

As I said before I will agree to disagree with you. I think that your unfounded allegations speak for themselves. Nothing personal, but between you and Citizen, I'll believe Citizen's engineers and customer service team, especially since they are stating in no uncertain terms that they will back their product regardless of the longevity of the power cell. Time will tell how long the cell lasts, your mileage may very. The technological excellence of their product speaks for itself and in my mind establishes their credibility to a very high order. I put my money on Citizen and will continue to do so until they prove otherwise.


----------



## NABodie (Jan 15, 2011)

Mine went about 15 yrs before it gave up the ghost. Guess I need to contact Citizen for a repair estimate.


----------



## Quark (Jul 1, 2010)

Not wanting to get in the middle of this but................

When Citizen says "you will never need to replace the battery" maybe they meant just that. You (personal pronoun) will never need to replace the battery. Not that it will never need to replaced. They will do it with their warranty.

On the longevity front companies use torture tests to cycle a product through many years of use in a short time.
As an example HP says its photo printer ink will last X-hundred years. How do they know that. They expose their prints to extreem Light conditions to represent years worth of exposure. And then interpolate the data to what that might be in years.

I'm quite sure Citizen has done similar testing and made a reasonable good faith guess. 

I don't know what my eco-drive will be doing in 18 years but my 6309-7040 and my BM will be going to the spa for an oil change and gaskets and then probably back to swimming and sailing at the beach.
And most of us will have flipped who knows how many watches.....Eco-Drives included.......by then.


----------



## South Pender (Jul 2, 2008)

robo21 said:


> Of course South Pender, we *all* care about "misrepresentation." However, we have not established that "misrepresentations" have been made in the least. Bottom line: You have no factual basis whatsoever to make these ridiculous and completely unfounded accusations of "misrepresentation" when there is no established track record as of yet. For all we know, their estimates are right on the money. Time will tell - no pun intended. From the tone of your posts it sounds as though you have an ulterior "axe to grind." I won't theorize on your numerous and redundant usages of the word "misrepresentation" throughout your posts except to say that repeating yourself doesn't make you any more believable nor credible.


No axe to grind. I've owned Citizen watches, thermocompensated quartz models and RC models for some time, and presently have two in my collection, both Chronomasters. I've been a big fan of Citizen and have touted the virtues of their watches, as my fellow HEQ forumers could readily attest.

It seems to me that your admission that "there is no established track record as of yet" supports the point I was making. Since there _is_ no track record, is it not just a little dishonest to claim that "the battery will never need replacement"? Again, as you yourself acknowledge, these assertions are nothing more than "their estimates" (your words). Unfortunately, estimates are not facts, yet the Citizen ads suggest the never-dying battery as a fact! The problem is not that I "have no factual basis whatsoever to make these ridiculous and completely unfounded accusations," but rather that Citizen has "no factual basis whatsoever to make these" unsubstantiated claims. Although you seem to object to the word "misrepresentation," I'm afraid that there isn't another that describes this better!



robo21 said:


> Nothing personal, but between you and Citizen, I'll believe Citizen's engineers....


It's not the engineers you're believing; it's the marketers! :-d


----------



## robo21 (May 26, 2011)

Quark said:


> Not wanting to get in the middle of this but................
> 
> When Citizen says "you will never need to replace the battery" maybe they meant just that. You (personal pronoun) will never need to replace the battery. Not that it will never need to replaced. They will do it with their warranty.
> 
> ...


Nice post Quark, finally a voice of reason in an otherwise obstreperous and belligerant thread. Clearly, Pender just wants to flame and argue which is why he uses inflammatory language, e.g. "misrepresentation." Absolutely ludicrous with no shred of evidence to back up this slander. Thank you for adding a calming note to the thread. Your outline of is exactly how such longevity estimates are made in the real world.

I'm done arguing with the troll.


----------



## South Pender (Jul 2, 2008)

robo21 said:


> Nice post Quark, finally a voice of reason in an otherwise obstreperous and belligerant thread. Clearly, Pender just wants to flame and argue which is why he uses inflammatory language, e.g. "misrepresentation." Absolutely ludicrous with no shred of evidence to back up this slander. Thank you for adding a calming note to the thread. Your outline of is exactly how such longevity estimates are made in the real world.


The only thing ludicrous is that someone would choose to believe marketing hype over the facts--which in the case of the longevity of the Citizen (or any other) solar-cell system are completely lacking. Psychologists refer to this irrational closure of the mind to facts (or their absence) as cognitive dissonance. One lays out some bucks for an item and, given the sacrifice, cannot now allow any "dissonant cognitions," or in plain language, discordant facts (or lack thereof) to be acknowledged.

I find it interesting that in Citizen's five-year warranty (for those models that have such a warranty), _the solar cell and rechargeable battery *are excluded*_. Does this suggest that Citizen really has a lot of confidence in their claim of unlimited battery life? In one Citizen ad, the marketing flacks claim: "Fueled by light, it never needs a battery." Never needs a battery? It comes with one, for pete's sake. Then the ad goes on: "It's unstoppable," which we are presumably to understand as 'the watch will never stop'--i.e., unlimited battery life again. Unadulterated marketing bumf. Anyone who actually believes any if this is displaying incredible naïveté!

For anyone interested, here's an excerpt from the warranty:

"Citizen Watch Company of America, Inc. ("COA"), with U.S. Service Headquarters at 1000 W. 190th street, Torrance, CA 90502 warrants this watch *(except the power cell, case and its components [including crystal, stem, crown], bracelet and its components [including clasp, links, pins, screws], strap and its components or any accessories)* to be free of defects in material and workmanship and to meet the timekeeping accuracy specification in the instructions for a period of five (5) years from the date of original retail purchase in the United States, Canada, Caribbean, Duty Free, and Military Exchange CITIZEN Watch Retailers authorized by COA." (Boldface mine.)

Never needs a battery? Unstoppable? Except when its power cell runs out! :-d


----------



## Quark (Jul 1, 2010)

South Pender.......If you are that sure they are using false advertising I guess you could always sue them and make a bundle because have been harmed by their claim.

On the other hand I have an Eco-Drive (2 years now), It is my most accurate watch I own though not my favorate. I'll PM you when it quits or in 18 years.

"fueled by light, it never needs a battery." Most people will understand that as meaning "another" battery knowing it comes with one.


----------



## robo21 (May 26, 2011)

South Pender said:


> The only thing ludicrous is that someone would choose to believe marketing hype over the facts--which in the case of the longevity of the Citizen (or any other) solar-cell system are completely lacking. Psychologists refer to this irrational closure of the mind to facts (or their absence) as cognitive dissonance. One lays out some bucks for an item and, given the sacrifice, cannot now allow any "dissonant cognitions," or in plain language, discordant facts (or lack thereof) to be acknowledged.
> 
> I find it interesting that in Citizen's five-year warranty (for those models that have such a warranty), _the solar cell and rechargeable battery *are excluded*_. Does this suggest that Citizen really has a lot of confidence in their claim of unlimited battery life? In one Citizen ad, the marketing flacks claim: "Fueled by light, it never needs a battery." Never needs a battery? It comes with one, for pete's sake. Then the ad goes on: "It's unstoppable," which we are presumably to understand as 'the watch will never stop'--i.e., unlimited battery life again. Unadulterated marketing bumf. Anyone who actually believes any if this is displaying incredible naïveté!
> 
> ...


Okay this is my last comment with the the troll. The exclusion of the power cell in this instance refers to NON ECO-DRIVE watches. COA will clarify this for anyone who is interested, give them a call. Later in the warranty is the following:


> What The Five Year Warranty Does Not Cover
> (a) Damage, accidental or otherwise, to the watch while in the possession of a consumer not caused by a defect in material or workmanship.
> (b) Damage caused by accident, misuse, tampering with or failure to follow the care and special handling provisions in the Instructions.
> (c) Damage and/or scratches to the finish of the case, crystal, bracelet, strap or other components caused by wear or accident.
> ...


Except Eco-Drive Hello - this is an indication that the warranty has specific exclusions for Eco Drive. COA customer service backs this up and I take them at their word. Of course they are going to exclude batteries in their non-Eco-Drive watches. This is another feeble attempt to cloud the issue and disparage Citizen.

One has to wonder what the motivation is in this case. Seiko fanboi? Troll? Probably both. Threatened by superior technology - maybe. It really doesn't matter.

I am posting this for the benefit of other readers on the forum. Do not be mislead by this Citizen hating troll. Clearly he has a huge investment in bad mouthing and slandering Citizen. Check the facts, contact Citizen.

Meanwhile, I will be back here every 5 years for the next 30 years to report on the battery longevity in my Citizens. ;-)


----------



## robo21 (May 26, 2011)

Quark said:


> South Pender.......If you are that sure they are using false advertising I guess you could always sue them and make a bundle because have been harmed by their claim.
> 
> On the other hand I have an Eco-Drive (2 years now), It is my most accurate watch I own though not my favorate. I'll PM you when it quits or in 18 years.
> 
> "fueled by light, it never needs a battery." *Most people* will understand that as meaning "another" battery knowing it comes with one.


"Most people" not trolls. From Wikipedia:


> In Internet slang, a *troll* is someone who posts inflammatory extraneous, or off-topic messages in an online community, such as an online discussion forum, chat room, or blog, with the primary intent of provoking readers into an emotional response or of otherwise disrupting normal on-topic discussion


----------



## South Pender (Jul 2, 2008)

Quark said:


> South Pender.......If you are that sure they are using false advertising I guess you could always sue them and make a bundle because have been harmed by their claim.
> 
> On the other hand I have an Eco-Drive (2 years now), It is my most accurate watch I own though not my favorate. I'll PM you when it quits or in 18 years.
> 
> "fueled by light, it never needs a battery." Most people will understand that as meaning "another" battery knowing it comes with one.


Well, the fact that it will never need "another" battery, as you allude (although "another" is, of course, not stated), is still false advertising, isn't it, given the empirical evidence available from owners who have had their eco-drives die out in a few years. As just one example, check Post #9 above. The accuracy of your watch is irrelevant; we're talking specifically about the expected lifespan of light-powered rechargeable batteries. That was, after all, the main question posed in the OP. Who wants to sue? The only persons "harmed by their claim" are those naive enough to believe it! :-d


----------



## South Pender (Jul 2, 2008)

robo21 said:


> The exclusion of the power cell in this instance refers to NON ECO-DRIVE watches.


Wrong. This warranty explanation came from the Eco-Drive webpage:

Welcome to Citizen Eco-Drive

It's too bad that you feel the need to engage in _ad hominem_ attacks, robo, and that your investment in a Citizen watch seems to have blinded you to the obvious (to most people) disconnect between advertising and empirical science.

The OP raised a question about the current state of light-powered battery-rechargeable cells, and the available evidence (_evidence_, not marketing nonsense), as incomplete as it is, is that none of them (Citizen's or those of other makers; my comments apply equally to Casio and Seiko light-powered cell systems, as seen in my Post #5 in which I was covering them generically) is likely to come anywhere close to having an infinite lifespan. The marketing would have you believe otherwise, but only the most naive would be taken in by this. One only has to review Post #9 above to see this, although there have been numerous threads on this forum and other watch forums that have documented the fatuousness of the claim. There was a recent thread on either this forum or the SCWF discussing whether or not eco-drive systems were superior to long-life, 10-year lithium batteries, with a number of forumers coming down on the side of the non-rechargeable 10-year batteries, given the documented problems with light-powered cells. It's a shame you didn't do your homework before blurting out your obviously erroneous views.

Since you have made a statement "for the benefit of other readers on the forum," I'll do the same: Do not believe, for even one nanosecond, the claims of Citizen, Seiko, Casio, and possibly others, that any light-powered rechargeable battery cell assembly will never need replacement. This is completely unsubstantiated marketing-based horsefeathers. The marketers know, of course, that the buying public would really like to believe this. From the small amount of actual evidence accumulated so far in the form of reported experiences of eco-drive owners, however, expect a typical cell to go, perhaps, 12-15 years. Some will do a little better; a lot will do less well, as we've seen evidence of even in this thread. Those are the _facts_ as we know them at this time.

However, robo, I'll leave it at that. Feel free to have the last word on this, as I'm sure you desperately wish to do so. :-d


----------



## tanwill (Jun 15, 2010)

Believed that if you have the battery charge and discharge normally, it should last you quite a while.

My first solar watch is a Valentino Domani and the battery lasted me 20 years before i had it changed (its a MT920).
I usually leave the watch by the windows if i dont wear it.


----------



## skyhawk818 (Sep 25, 2010)




----------



## robo21 (May 26, 2011)

Agreed Skyhawk818. Nice video BTW. Trying to engage this (






) guy in a discussion is basically having a battle of wits with an unarmed man. Pointless.

I'll be happily placing my order this week for yet another Eco-Drive BL5250-02L, I am not in the least bit worried about the longevity of these fantastic timepieces *or *their power cells.


----------



## skyhawk818 (Sep 25, 2010)

BL5250-02L??? Are you serious? Are you feeling Faint? Do you need a Doctor?

There are still a few Skyhawk Variants that you still do not own....


----------



## robo21 (May 26, 2011)

skyhawk818 said:


> BL5250-02L??? Are you serious? Are you feeling Faint? Do you need a Doctor?
> 
> There are still a few Skyhawk Variants that you still do not own....


LOL Skyhawk818, how many Skyhawks do I need? Wait... Last time I checked you have only 2... lol I really like the BL5250 but it will be a safe bet when the 4th generation Skyhawks come out I'll be right there with the newest Blue Angels and Skyhawk A-T orders.


----------



## mikeynd (Dec 11, 2008)

It doesn't even pay to argue with South Pender,,He is pretty well known to do this in the HEQ forum,and he is never wrong,,lol
I am not sure why he is getting all tissy over Citizen's marketing..


----------



## Quark (Jul 1, 2010)

South Pender said:


> Well, the fact that it will never need "another" battery, as you allude (although "another" is, of course, not stated), is still false advertising, isn't it, given the empirical evidence available from owners who have had their eco-drives die out in a few years. As just one example, check Post #9 above. The accuracy of your watch is irrelevant; we're talking specifically about the expected lifespan of light-powered rechargeable batteries. That was, after all, the main question posed in the OP. Who wants to sue? The only persons "harmed by their claim" are those naive enough to believe it! :-d


If you are not harmed by their advertizing why are you so adament about whether or not the advertizing is false or not.

As far as I know this is a discussion/opinion web sight. So my comment about the accuracy of my Eco-Drive while off topic still allowable. You seem to focus your thoughts and anger at partial or misunderstood parts of phrases or comments or advertizements. While you quoated me saying my comment was irrelevent the rest of the statement that I would let you know when it fails or when it reaches 20 years was ignorred. I was offering empirical evidence when it was available. That after all is the only way we will come to the end of this arguement.

And then I'm not sure what your gripe is. I'm assuming you don't have an Eco-Drive, you are way out in front of their false advertizing claims, then you haven't been harmed. So what is your point?

As far as "another" battery is concerned everybody on earth living, other than perhaps in the third world, knows that solar watches run on a "battery charged by solar" or it would not run when night comes or the lights are turned off. Therefor that it already has a battery is understood by all and does need to be stated.


----------



## robo21 (May 26, 2011)

mikeynd said:


> It doesn't even pay to argue with South Pender,,He is pretty well known to do this in the HEQ forum,*and he is never wrong,,lol*
> I am not sure why he is getting all tissy over Citizen's marketing..


LOL first time for everything. Too bad really.



Quark said:


> If you are not harmed by their advertizing why are you so adament about whether or not the advertizing is false or not.
> 
> As far as I know this is a discussion/opinion web sight. So my comment about the accuracy of my Eco-Drive while off topic still allowable. You seem to focus your thoughts and anger at partial or misunderstood parts of phrases or comments or advertizements. While you quoated me saying my comment was irrelevent the rest of the statement that I would let you know when it fails or when it reaches 20 years was ignorred. I was offering empirical evidence when it was available. That after all is the only way we will come to the end of this arguement.
> 
> ...


Naturally Quark he is going to pull things out of context in an attempt (feeble at that) to denigrate Citizen (and now other watchmakers) without a shred of evidence beyond his own opinions and projections. Even his references to the warranty are not based on reality as COA is replacing power cells even beyond the 5 year warranty (actually for the life of the watch) when and if needed. Unless you enjoy and endless cycle of fruitless arguing and nitpicky bickering any attempt at discussion is a waste of time. I think at this point this thread should be closed. 
The ugliness has gone on too long and this discussion is generating more heat than light. :-(


----------



## South Pender (Jul 2, 2008)

You guys are a lot of fun. :-d For anyone still interested in the opening question--which is a good one--here are some earlier discussions and information on the topic:

https://www.watchuseek.com/f2/lifespan-solar-powered-watches-173481.html

https://www.watchuseek.com/f21/ecodrive-versus-long-life-lithium-battery-513835.html

http://www.citizenwatch.jp/faq/faq.htm#01


----------



## 2500M_Sub (Apr 12, 2008)

Ok guys, lets all calm down. I dont think South Pender was trying to be a troll he just has a different point of view. South Pender, welcome to the world of advertising,never need a battery" is like "100,000 mile warranty", marketing hype. Now lets all play nice. 

Regards,

Ren


----------



## asfalloth (Feb 22, 2006)

Not wishing to stir up the hornets nest again, but just to add I bought a Eco-Drive Chronograph in 1994 thats still going strong now:-!

It doesnt get much wrist time mind you, but gets plenty of bathroom windowsill time:-d


----------



## petew (Apr 6, 2006)

That's an amazing watch. Citizen says they didn't even make plain Eco Drives in 1994 let alone chronographs. Do you have a pic?


----------



## Catalin (Jan 2, 2009)

petew said:


> That's an amazing watch. Citizen says they didn't even make plain Eco Drives in 1994 let alone chronographs. Do you have a pic?


Some models might have started very early in JP - 'simple' models in 1994 and chronographs in 1995:

Google Translate

Google Translate

Google Translate

Google Translate


----------



## asfalloth (Feb 22, 2006)

Well Im obviously mistaken then, could've sworn it was a year or two before I met my wife in 96, I'll post a pic non the less


----------



## petew (Apr 6, 2006)

1995 was the first year Citizen used "EcoDrive" on watch dials and casebacks. They had solar models for years before (for example, that 1994 Solar Oxy in your link) but never using the "EcoDrive" terminology. I don't think they sold a Chronograph with EcoDrive on the dial (outside of Japan) for at least a year after that.


----------



## asfalloth (Feb 22, 2006)

My wife says 1998, profuse apologies for my mistake


----------



## robo21 (May 26, 2011)

asfalloth said:


> Well Im obviously mistaken then, could've sworn it was a year or two before I met my wife in 96, I'll post a pic non the less


Heck, even if it was '96 or '97 that's still good mileage. Your serial number should reveal the build date of the watch. Is it your JY0075-54E that you are referring to?


----------



## petew (Apr 6, 2006)

Thanks for the shots. That's got to be one of the oldest if not the oldest eco-chronos on this forum.

Very cool!


----------



## robo21 (May 26, 2011)

Nice watches!


----------



## asfalloth (Feb 22, 2006)

robo21 said:


> Heck, even if it was '96 or '97 that's still good mileage. Your serial number should reveal the build date of the watch. Is it your JY0075-54E that you are referring to?


The serial on the old one is 880361.

Only just got the JY0075, loving it:-!


----------



## robo21 (May 26, 2011)

You're not the only one who loves that watch (54E) evidently - every single review on Amazon gives it 5 stars! I believe the sn you posted confirms a '98 mfg date.


----------



## Mark II (Oct 9, 2011)

South Pender said:


> No need for this personal tone, robo21. Nonetheless, let me say that since there is absolutely no empirical evidence pointing to _what_ will be the case in 20 years (let alone 80% of the charge) vis-a-vis remaining charge levels, any claim is an hypothesis--or, in ordinary-language usage, speculative. It's a guess presented as though it were a fact. Citizen are certainly not alone in misrepresenting the facts about their products. If you consider the mileage claims made by almost all car manufacturers these days, you will find exactly the same thing. Vehicles that under extremely-artificial circumstances achieve a certain mileage are portrayed as yielding this mileage as a matter of course. A car advertised to give 40 mpg in a magazine or TV ad will, instead, yield about 30 mpg in a realistic driving test such as those (100-mile test drives) conducted by the Consumer's Union and reported in _Consumer Reports_. This is misleading advertising and, in my opinion, should be shut down (although I don't expect to see that). Citizen is doing much the same thing (and other watch companies are probably doing this too) by claiming that "the battery will never need replacement." Any claim about performance needs to be grounded in empirical evidence. The 80% left in 20 years has no real empirical support.
> 
> The fact that Citizen _may_ replace a defunct battery (and that too requires a large leap of faith in my opinion) in no way excuses them for misrepresentation in the first place. If they had said something like "batteries will be replaced free of charge by Citizen," this would be honest. But to anyone who respects honesty and wants truth in advertising, Citizen's corporate behavior regarding replacement is pretty much irrelevant. Many of us _do care_ about misrepresentation, regardless of corporate efforts to satisfy customers.
> 
> ...


----------



## Sabresoft (Dec 1, 2010)

South Pender said:


> Vehicles that under extremely-artificial circumstances achieve a certain mileage are portrayed as yielding this mileage as a matter of course. A car advertised to give 40 mpg in a magazine or TV ad will, instead, yield about 30 mpg in a realistic driving test such as those (100-mile test drives) conducted by the Consumer's Union and reported in _Consumer Reports_. This is misleading advertising and, in my opinion, should be shut down (although I don't expect to see that).


To be fair these unrealistic gas mileages are based on the EPA test cycle in the US (I'm not sure what we use in Canada). Car companies using these numbers can't really be accused of false advertising as these are government sanctioned numbers. Besides they can be replicated if the driver is willing to make the necessary sacrifices.



South Pender said:


> Finally, how do you square your views about the likely lifespan of solar-cell/battery units with petew's actual, empirical experiences? Doesn't seem like 80% left in 20 years has panned out in practice....


Can't speak to 20 years, but I have 10 years experience with my older Skyhawk and the battery has so far performed flawlessly. It did go back to Citizen last year to get the chronograph pushers cleaned as they were sticking, but there was no indication that they replaced the battery at that time (but they may have done so proactively). In fact until recently it was never less than fully charged as it was worn daily. Now that it sits in a rotation of about a dozen watches it spends a lot of time in a drawer and has dropped below three bars a few times.

In fact it was while the older Skyhawk was off for repairs that this watch habit was hatched. I felt naked without the Skyhawk, but there were just too many great watches out there to settle on only one.


----------



## watchn0ob (Oct 3, 2011)

I've got a citizen given to me in 1998 which is still going strong.


----------



## CitizenM (Dec 9, 2009)

Ok, let's settle down. South Pender is not a troll.

There are a few issues with the 20 years claim of Citizen. Notably, as others have pointed out, there's a lot more involved in the longevity of a watch than the battery. It's just the battery is the part that we're used to initially breaking down and being the major source of annoyance in quartz movements. Actually, batteries are much better today than they were awhile back. I have a mid priced Fossil quartz beater that's going on over 5 years on the original battery now (granted, that watch has a Citizen movement in it, I believe, but it's still a conventional battery). Now you can buy 10 year batteries and so on. I wouldn't be surprised if a 10 year battery lasted 12.

But there are relevant counterpoints. Seiko, by far the most respected producer of quartz movements, claims that its 9F movements can go one half a century between services. Now, we're not suggesting that $200 eco-drive movement (and seals and so on) is going to go toe to toe with a Grand Seiko, but it it's at least possible that a modern, high quality quartz movement, which we all agree Citizen utilizes, could make it 20 years.

Indeed, there is a great deal of anecdotal evidence that the eco-drive watches are making it into the 15 year range before failure.

Of course, we need to narrow down our claim. Is our claim that the _battery_ will last 15+ years? Or that the watch will work. These are very distinct claims. Notably, many posters make the error of constantly exposing their Citizens to direct sunlight in an attempt to keep the battery fully charged. Indeed, this will contribute to battery longevity. Unfortunately, the solar cell's efficiency will be vastly diminished by constant exposure to sun light. The short life of solar cells is a major drawback in their use.

I don't know what the proper balance of battery maintenance to solar cell maintenance would be. I'm not sure which will fail first.

I like eco drive. The battery system lasts, as a matter of routine, far longer than a conventional battery, and it lacks the moving parts of kinetics or automatics, so I can practice sports and things with my eco drive on without much concern.


----------



## Sabresoft (Dec 1, 2010)

Marketing claims can be unrealistic, and Citizen is not immune. The advertising for my older Skyhawk claimed that the watch could sit in the dark for 5 years and still keep the time. Several years later the claim for the very same model was reduced to 4 years. 

So in the context of the OP's question, South Pender's questioning of marketing claims for solar watch batteries is not trolling. Also as he has indicated that he owns several Citizen watches he hardly strikes me as a Citizen hater. 

I own five Citizen (six if you count the Bulova Precisionist) watches, and will buy more again in the future, but I agree that some of their marketing claims are suspect. Unfortunately so are the claims of many other brands.


----------



## CitizenM (Dec 9, 2009)

Wow, I didn't even realize this was a dead thread...boy is my face red


----------



## steed68 (Jul 29, 2011)

I think we are splitting hairs here,even if my Eco-Drive's cell lasts five years I'm still farther
ahead than with a regular quartz watch even if I have to pay a bit extra for the 200m pressure
test.Also having had to go through the winding and periodic cleaning hassles of automatics,I'd
say these watches are the best quality for the money even if the claims are stretched a bit.


----------



## rcorreale (Jan 25, 2008)

I think the "never needs a battery" claim is in comparison to most conventional battery powered watches that need their batteries replaced every 2-3 years.

Nothing more, nothing less.

Even if the solar rechargeable battery dies after 10 yrs. and you have to pay 50-100 bucks to get the movement cleaned and seals changed, you're still ahead of the game assuming the rest of the watch is in good working order.

My OP anyway.


Sent from my iPhone using Tapatalk


----------



## Dch48 (Apr 10, 2012)

The Eco-Drive technology is not new and has been around for more than 20 years already. I trust that Citizen will replace the battery free of charge but may charge for some of the other things mentioned. Most people will not have an Eco-Drive serviced because it simply won't need it so Citizen may wiggle out if the watch has never been looked at after 10-15 years or longer. Such a watch will be much cheaper to keep going for 20 years than any mechanical watch out there even if you do get charged for a battery replacement or two.

In the case of mileage on cars, when they test a car and give out those MPG figures, they do it with no lights on, no A/C running, tires possibly a little overinflated but certainly not under at all, driving at the optimal speed which can vary from model to model,and nothing that requires any electricity turned on. I have no doubts that the numbers released are accurate but very few, if any, actual drivers will achieve the same figures.


----------



## petew (Apr 6, 2006)

Dch48 said:


> In the case of mileage on cars, when they test a car and give out those MPG figures, they do it with no lights on, no A/C running, tires possibly a little overinflated but certainly not under at all, driving at the optimal speed which can vary from model to model,and nothing that requires any electricity turned on. I have no doubts that the numbers released are accurate but very few, if any, actual drivers will achieve the same figures.


Actually this is not true. EPA drastically changed their mileage measurements quite a few years ago. Here's a link:

Regulatory Announcement: EPA Issues New Test Methods for Fuel Economy Window Stickers | Fuel Economy | US EPA

I think for every car I've owned, my experience has exceeded the EPA measurements.


----------



## Pete26 (Feb 17, 2006)

petew said:


> A few points....I know that folks have had batteries replaced from Citizen and they've been charged. Maybe not for the battery, but for a pressure test, new seals, movement lubrication...something....so I'm not 100% convinced that you could send an eco to COA and say ....just replace the battery and do nothing, and get a free service. They may insist on pressure testing and new seals. I'd be interested in hearing some thoughts on this.
> 
> One thing not mentioned is the lifespan of the solar cell. Those have finite lifespans as well....but...we don't know how long. I've recently noticed that at least on their Japanese site, Citizen is specifically stating that these cells will require periodic replacement.
> 
> I've had more than a couple of Eco's fail on me so I'm not as convinced as others as to there invincibility. They go in funny ways too. They stop, you do a reset, put them outside in the sun and they start right up and seem to run fine. A month later, you look at them and see that they had stopped again at some point. Mine are always kept in a bright sunny room so they get plenty of light and aren't going through drastic recycling.


My wifes did that after 8 years, it stops periodically, but charges in direct sunlight only to die again after being left on a wardrobe

Cheers

Pete


----------



## Pete26 (Feb 17, 2006)

asfalloth said:


> My wife says 1998, profuse apologies for my mistake


Don't let your wife know you forgot what year you met


----------



## por44 (Dec 21, 2007)

Bottom Line: Based on 15+ years of service - the performance has been 1st class.

Wouldn't it be interesting if some upscale brands could use it or an equivalent?


----------



## got6ponies (Jan 31, 2011)




----------



## Beginnersmind (Apr 20, 2012)

First, I love Citizen watches, great bang for the buck! And I like the eco-drives. My understanding (maybe wrong) is that the power cell in the eco-drive watches is referred to as a "capacitor" and not as a battery, so no you never have to replace a battery, just perhaps the capacitor! My personal experience with rechargeable quartz watches was with one of the first Seiko kinetics. It stopped after 10 years but it never charged correctly from the beginning (but it did charge well enough that I didn't bother pursuing warrantee service.) I put a new capacitor in it and it ran great then I flipped it so I don't know how it is doing now. When it started to go it simply couldn't hold a charge more than a few hours off my wrist but worked fine while I was wearing it and was active. Just fyi.


----------



## paj20 (Jan 6, 2010)

15 years for my 1998 Eco-Drive chronograph, and still running..!

View attachment 1012972


----------



## dcdude (Apr 29, 2012)

South Pender said:


> One important factor is whether the battery is subjected to a number of "full recharges," such as when it runs down completely (or nearly completely) and has to be recharged a long way back to full charge. The rechargeable battery will take only so many of these before giving up. The standard recommendation from the watchmakers is to try to keep the battery "topped up"--that is, never let it go down too far, but instead keep the watch exposed to light all the time (or nearly all the time).


This seems contrary to what I've learned about rechargeable batteries in other applications. Most of us have heard of the "memory effect" of partial charging, probably in the context of mobile phones. I expect that an Eco-Drive purchased today in 2013 would have lithium ion or similar technology, which I understand is much more resistant to memory effect. Nevertheless, all rechargeable batteries have a limited number of cycles. It would seem to me then, that full charge followed by full discharge would minimize the number of lifetime cycles and thus be the best practice for any battery-powered device, regardless of chemistry.


----------



## Pawl_Buster (Mar 12, 2007)

dcdude said:


> This seems contrary to what I've learned about rechargeable batteries in other applications. Most of us have heard of the "memory effect" of partial charging, probably in the context of mobile phones. I expect that an Eco-Drive purchased today in 2013 would have lithium ion or similar technology, which I understand is much more resistant to memory effect. Nevertheless, all rechargeable batteries have a limited number of cycles. It would seem to me then, that full charge followed by full discharge would minimize the number of lifetime cycles and thus be the best practice for any battery-powered device, regardless of chemistry.


What South Pender is talking about when he says '_never let it go down too far'; is the battery dropout voltage. Watch makers have set the two second shuffle to be safely above this level so if the watch is not allowed to completely discharge there should be little ill effects. However; any time the battery is allowed to discharge below this level; degredation starts and the useful life of the battery can be severely reduced._


----------



## Citizen V (Jun 29, 2011)

dcdude said:


> This seems contrary to what I've learned about rechargeable batteries in other applications. Most of us have heard of the "memory effect" of partial charging, probably in the context of mobile phones. I expect that an Eco-Drive purchased today in 2013 would have lithium ion or similar technology, which I understand is much more resistant to memory effect. Nevertheless, all rechargeable batteries have a limited number of cycles. It would seem to me then, that full charge followed by full discharge would minimize the number of lifetime cycles and thus be the best practice for any battery-powered device, regardless of chemistry.


The memory effect is for mainly for NiCd rechargeable batteries, while Eco-Drives do use Li-ion batteries. One main advantage of Li-ion batteries is the lack of memory effect, not just more resistance (although there apparently were findings from earlier this month that suggest that there is actually a tiny memory effect: memory effect now also found in lithium-ion batteries). Additionally, full discharges are bad for lithium ion batteries. This site had a good chart for discharges and cycles:
How to Prolong Lithium-based Batteries - Battery University


----------



## pfarrec (May 15, 2013)

I have had my Citizen Eco Drive for 7 years, and it now will no longer recharge. COA is quoting me $83 to fix it. Seems a bit ridiculous to me. The warranty only covers the watch for 5 years. If any sales person tells you otherwise, they are lying.


----------



## johnj (Apr 13, 2006)

robo21 said:


> Agree as to full discharge/recharge cycles diminishing lifespan of rechargeable battery. But in my mind,* I* will *never* have to replace a battery in my Eco Drive watch. Citizen has given me their assurance that the battery is covered for the life of the watch. COA may have to replace the battery but not me. So it's *not* marketing hype. They say "Never needs a battery" and I choose to take them at their word.


If you look in your watch manual, it should give the recommended battery change interval for the eco-drive rechargable battery. And it's not that many years.


----------



## Mudman001 (Jul 3, 2008)

The Key is dont let it completely die then expect it to hold a charge the same way again after being recharged. That being said ive had the BN0000 for about 9 yrs. I left it in my Dive gear bag completely forgetting about the watch being in the bag. I have a large collection of watches so it doesn't get worn as much as it should to keep it charged. Once I realized where the watch was it was completely discharged. I put it in a Window sill that gets sun through it all day for like a week and it has held a charge very very well ever since and that was 5 yrs ago now. Like other's have said it depends on several factors. One being don't let it go dead and another is don't subject the watch to impacts that can jar things loose in the case that keeps the watch charged. Me personally, ,, ive been VERY VERY impressed with the technology. And really.. to keep it charged you don't have to leave it in the Window all the time. Just wear it or when it's not being worn keep it in an area of the house that's lit up normally. It takes very little light to keep them charged and running normally. The one thing I would not suggest is to keep it in a box or drawer that is completely dark all the time. Cause in 5 to 6 months depending on what model you have it will be dead as a doornail. And the more time it's completely discharged then recharged the less the storage battery will last. 

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2


----------



## RejZoR (May 12, 2010)

Actually batteries used in watches are mostly Lithium-titanate which is even more durable than any other Lithium based rechargeable battery.

Plus, the main problem with batteries is the rate at which they charge. The faster it is recharged, the more it gets damaged. The stuff with electrons and heat generated. Batteries don't like heat. Solar cells in Eco-Drives charge the Li-Ti-Ion battery at very slow rate, meaning it won't heat up much. So thats good


----------



## Mudman001 (Jul 3, 2008)

RejZoR said:


> Actually batteries used in watches are mostly Lithium-titanate which is even more durable than any other Lithium based rechargeable battery.
> 
> Plus, the main problem with batteries is the rate at which they charge. The faster it is recharged, the more it gets damaged. The stuff with electrons and heat generated. Batteries don't like heat. Solar cells in Eco-Drives charge the Li-Ti-Ion battery at very slow rate, meaning it won't heat up much. So thats good


Well said.

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2


----------



## pbubsy (Nov 21, 2008)

I have one that's been going strong for around 10 years. No worries!


----------



## oiram (May 25, 2010)

I have a Skyhawk that has been running strong for about 10-11 years. I use it as a gym watch and leave it by a window to collect the light the rest of the time. I have never had a problem with it.


----------



## Pete26 (Feb 17, 2006)

My wife's eco-drive cost $175 to fix. They claimed it needed a service and would be good for another 5 years. Sounds like they got it confused with an automatic. They are Brisbane's authorized Citizen repairer.

Sent from my Galaxy Nexus using Tapatalk 4 Beta


----------



## serge70 (Nov 16, 2010)

Yes,it surely does.In my personal experience [at least in the UK] Citizen & Seiko service centres offer horrible service,are run on a shoe-string & the technical knowledge of the staff is dire.

If my Eco-Drive expires I shall attempt to replace the capacitor myself & if that fails will go buy a new one.

Anything but sending to Citizen for "service".


----------



## Andrew McGregor (Dec 27, 2011)

RejZoR said:


> Actually batteries used in watches are mostly Lithium-titanate which is even more durable than any other Lithium based rechargeable battery.
> 
> Plus, the main problem with batteries is the rate at which they charge. The faster it is recharged, the more it gets damaged. The stuff with electrons and heat generated. Batteries don't like heat. Solar cells in Eco-Drives charge the Li-Ti-Ion battery at very slow rate, meaning it won't heat up much. So thats good


Lithium Ion batteries are actually endothermic on charge, meaning they absorb heat as they charge. But anyway, charge or discharge rate is not a factor for a watch battery, it's so low.

On the other hand, no lithium battery likes deep discharge... they are much better with frequent shallow cycles, since they do not have memory effect. That's why Citizen use batteries big enough for 6 month power reserves; discharging no more than 0.7% a few times a day is by far the best cycle pattern for lithiums.

Eco-drives are very highly optimised for best possible battery life.


----------



## adlu (Jan 27, 2019)

petew said:


> A few points....I know that folks have had batteries replaced from Citizen and they've been charged. Maybe not for the battery, but for a pressure test, new seals, movement lubrication...something....so I'm not 100% convinced that you could send an eco to COA and say ....just replace the battery and do nothing, and get a free service. They may insist on pressure testing and new seals. I'd be interested in hearing some thoughts on this.
> 
> One thing not mentioned is the lifespan of the solar cell. Those have finite lifespans as well....but...we don't know how long. I've recently noticed that at least on their Japanese site, Citizen is specifically stating that these cells will require periodic replacement.
> 
> I've had more than a couple of Eco's fail on me so I'm not as convinced as others as to there invincibility. They go in funny ways too. They stop, you do a reset, put them outside in the sun and they start right up and seem to run fine. A month later, you look at them and see that they had stopped again at some point. Mine are always kept in a bright sunny room so they get plenty of light and aren't going through drastic recycling.


Thanks for all the good info on this forum! First time visitor and poster. This is an old thread, but I wanted to share a recent (Jan 2019) experience with COA in case it's useful to anyone.

I have an Eco-drive Stilleto from ~2003 that performed perfectly for nearly ten years. I stopped wearing it in ~2012 and kept it in a dark place until 2018 when I wanted to wear a watch again. I kept it on a sunny windowsill for several weeks straight, and it only ran for ~10 hours. My local authorized Citizen dealer submitted the serial number to COA, who responded that the energy cell was covered by the limited lifetime warranty.

As you predicted, COA did NOT give me a free repair. They insisted on changing the movement and gasket, which cost $120. I went through the authorized dealer, so I don't have the exact documentation from COA, but the dealer said that they replaced the entire innards, so I essentially have a new watch. I'm skeptical, but I figured $120 was still better than buying a new watch, so I did it.

I'll be sure to follow the common advice of keeping the watch in a well-lit spot even during periods when I'm not wearing it. Thanks again for everyone's advice!


----------



## adlu (Jan 27, 2019)

South Pender said:


> You guys are a lot of fun. :-d For anyone still interested in the opening question--which is a good one--here are some earlier discussions and information on the topic:


I'm a first-time reader and poster, and I have no skin in the game or previous knowledge of any of these posters, but I just wanted to say to South Pender that I do appreciate your point (that Citizen's marketing needs to be taken with a grain of salt), as well as your useful post here.

At the very least, Citizen should provide clearer instructions with their watches on best practices for maintaining power cells, i.e., keeping them charged up even during long periods of not wearing them. Making sure that all their customers understood this point would have reduced their warranty claims and kept disappointment at a minimum.


----------



## TwentiethCenturyFox (Mar 8, 2014)

More than a year.


----------



## JMullins (Oct 12, 2020)

We're missing some basic electrical engineering. Citizen cannot replace the battery on ecodrive watches, because it does not have one. It uses a capacitor to store energy. This is a very different device than a battery. Though it is rare, it can fail. When it does, it can be replaced. My first citizen had been running for 13 years now, and it is showing some wear, but has not been set in many years. It just keeps time. The movement is likely to last longer than the glass or the body.


----------



## Sclsdagnd (Aug 26, 2020)

JMullins said:


> We're missing some basic electrical engineering. Citizen cannot replace the battery on ecodrive watches, because it does not have one. It uses a capacitor to store energy. This is a very different device than a battery. Though it is rare, it can fail. When it does, it can be replaced. My first citizen had been running for 13 years now, and it is showing some wear, but has not been set in many years. It just keeps time. The movement is likely to last longer than the glass or the body.


Eco Drive watches use Li-ion batteries, but for some (probably historical) reasons people call them capacitor. AFAIK some Seikos did use capacitors, but those had quite short power reserve (about a week) and they were quite unreliable. Modern Eco Drives mostly use manganese titanium or cobalt titanium rechargable lithium batteries.


----------



## Mr. James Duffy (Feb 2, 2016)

A lot of the early solar-powered technology in watches were indeed capacitors and some featured a low-capacity backup battery. The industry seems to have moved completely to a lithium-based rechargeable battery. I just replaced the battery in a 15 year old Casio Tough Solar movement and it used a cobalt titanium lithium ion battery.


----------



## JMullins (Oct 12, 2020)

Maybe the historical reason they are called capacitors, is that they had capacitors. My old citizen still has a capacitor and keeps good time. I also have a new Citizen with a battery, they claim it will have a life of 40 years. I don't much care if that's true, the watch will likely be too worn long before then anyway.



Sclsdagnd said:


> Eco Drive watches use Li-ion batteries, but for some (probably historical) reasons people call them capacitor. AFAIK some Seikos did use capacitors, but those had quite short power reserve (about a week) and they were quite unreliable. Modern Eco Drives mostly use manganese titanium or cobalt titanium rechargable lithium batteries.


i


----------



## spacey_g (Oct 29, 2020)

South Pender said:


> Nonetheless, let me say that since there is absolutely no empirical evidence pointing to _what_ will be the case in 20 years (let alone 80% of the charge) vis-a-vis remaining charge levels, any claim is an hypothesis--or, in ordinary-language usage, speculative. It's a guess presented as though it were a fact.


I realize this comment is nearly a decade old, however it's an interesting discussion.

I would point out that it's possible to test the lifespan of a product or component without actually using it for the full time. There are various methods of accelerated aging and the rechargeable cell in an Eco-Drive watch is a good candidate for this type of testing. Citizen would simply need to charge and discharge the cell over and over until the capacity degrades to some specified level--in this case 80%--and then determine how long it would take for the typical watch movement to use that number of charge cycles.

This type of test could be done much more quickly than the 20 years it would take to cycle the cell in a watch, and would likely give a conservative estimate of the lifespan of the cell. This is certainly empirical evidence and worth an awful lot more than a "guess". I suspect Citizen used a method similar to this to come up with the 20 years/80% figure.


----------

