Do I need a new one?

[JSWolf]

Originally Posted by Hollow Man

We get it...you don't like it. None of us have evidence yet to support this (since the product is still very new), but my opinion is that most people wouldn't notice any loss of battery life, until they got to 10 years or so of use. And who cares after that long?! If one is the sort to spend this much on a Kindle, just buy the new one again!

-HM

Of course we have evidence to support this. It's how lithium-ion batteries work.

Originally Posted by barryem

I have a Voyage. I considered getting the Oasis but fortunately they ran out before I ordered one so I had to wait and while I waited I thought about that battery. The internal battery in the Oasis is 1/6 the size of the battery in the Voyage. The cover provides additional capacity but it only keeps the internal battery charged. The Oasis isn't powered by it.

Since a typical battery is good for between 500 and 1000 charges that internal battery should use up it's lifetime of charges 6 times faster. And that's why I don't have an Oasis.

This says it all.

[Hollow Man]

Originally Posted by JSWolf

Of course we have evidence to support this. It's how lithium-ion batteries work.

Note I didn't say it's not what happens...I said most people wouldn't notice.

-HM

[JSWolf]

Originally Posted by Hollow Man

Note I didn't say it's not what happens...I said most people wouldn't notice.

-HM

I think they would notice.

[NullNix]

Originally Posted by JSWolf

Of course we have evidence to support this. It's how lithium-ion batteries work.

I have repeatedly pointed out that it's not in fact how lithium-ion batteries work, but you have ignored me every time. (I gave references in the past, but you ignored them then, and I can't be bothered any more. You're ineducable.)

[JSWolf]

Originally Posted by NullNix

I have repeatedly pointed out that it's not in fact how lithium-ion batteries work, but you have ignored me every time. (I gave references in the past, but you ignored them then, and I can't be bothered any more. You're ineducable.)

So it's not true that lithium-ion batteries have a certain number of charges and when you have to charge more you get less time with the battery before you can tell it isn't holding as much power?

[NullNix]

Originally Posted by JSWolf

So it's not true that lithium-ion batteries have a certain number of charges and when you have to charge more you get less time with the battery before you can tell it isn't holding as much power?

It's not true. That's not how lithium-ion battery chemistry works. There is no counter, as you seem to believe. Amazon are not idiots and did actually design this thing to not die after a year and piss all their highest-spending Kindle customers off.

What happens is that *deep discharges* and the resulting long rapid charges cause plating of lithium metal on the electrodes (anode or cathode depending), and once it's plated it drops/flakes off and, well, there's no way to get that lithium metal back into ionic solution again, so the capacity of the battery drops. For most Kindles, this is how the battery is usually used unless you really like recharging it, but not the Oasis internal battery. Short, frequent charges and discharges of a mostly-full battery -- the predominant mode of use of the Oasis internal battery -- have very nearly no effect on battery life. There *is* an effect, but we're talking so many tens of thousands of charges and discharges that I haven't been able to find any research that has driven it to completion with, say, 10% or 20% charge/discharge cycles: they let it drop about 20%, enough that they're not guessing too much at the shape of the curve, and extrapolate. This does not affect internal voltage levels of a non-full battery, so what you see is that the battery appears less than 100% full when it is actually full: the battery seemingly won't charge all the way any more.

At shallow discharge levels, the effect of plating is probably much smaller than the slow internal resistance increase caused by simply keeping the thing in an oxygen atmosphere (that's the effect that causes it to run out of power when there's still 30% reported as left, or whatever -- though in practice battery circuitry will compensate for this, but if it didn't that's what you'd see). It starts getting significant if you drop the battery to maybe 30% total charge on a frequent basis: 50% seems to be fairly insignificant, but as you can tell from the woolly wording the data is very fuzzy at this point and is confounded by all sorts of factors.

So given my Oasis usage patterns (replace in cover while not using, internal battery fluctuating around 70--95% charge) I expect to have to replace the *cover* due to plating eventually (I never bother to charge the thing until the cover is nearly empty), but the Oasis itself? Naah. The battery will die after a decade or so from internal oxidation, only by then it will be totally obsolete. Say rather that obsolescence will cause me to replace it, not battery capacity loss.

[Sweetpea]

Originally Posted by Hollow Man

We get it...you don't like it. None of us have evidence yet to support this (since the product is still very new), but my opinion is that most people wouldn't notice any loss of battery life, until they got to 10 years or so of use. And who cares after that long?! If one is the sort to spend this much on a Kindle, just buy the new one again!

-HM

that 10 years is a bit on the very optimistic side of things... Generally, for more power-hungry devices (think phones and tablets), you'll notice a degradation after about a year or so. For a less power-hungry device (such as ereaders), it might be 5 years before you notice a degradation. My BeBook Mini (from around 2009) really started showing its battery age about 2 years ago. It wouldn't hold a charge for more than 2 weeks anymore (default drain, without using it)

[NullNix]

Originally Posted by Sweetpea

that 10 years is a bit on the very optimistic side of things... Generally, for more power-hungry devices (think phones and tablets), you'll notice a degradation after about a year or so. For a less power-hungry device (such as ereaders), it might be 5 years before you notice a degradation. My BeBook Mini (from around 2009) really started showing its battery age about 2 years ago. It wouldn't hold a charge for more than 2 weeks anymore (default drain, without using it)

The question is why it is degrading. The degradation you see in the power-hungry devices is probably due to loss of lithium ions due to plating from deep discharges/charges: the figure I gave is a (very) rough ballpark figure for internal resistance due to oxidation, which is a much slower effect. This proceeds regardless of battery use and charge levels, so the 5 years you report for the non-power-hungry device may be down to this (5 years, 10 years, basically the same: ballpark figure, remember ).

[Hollow Man]

My point was that most people aren't going to see a serious decline in battery life before they decide to stop using the device permanently. If they use the device all the time, the battery gets proper "exercise". If they use it sparingly, then even if there are deep discharges, it isn't enough to affect to affect life.

Nutshell: if someone notices an issue, by that time they're ripe for a new Kindle.

-HM

[Sweetpea]

Originally Posted by NullNix

The question is why it is degrading. The degradation you see in the power-hungry devices is probably due to loss of lithium ions due to plating from deep discharges/charges: the figure I gave is a (very) rough ballpark figure for internal resistance due to oxidation, which is a much slower effect. This proceeds regardless of battery use and charge levels, so the 5 years you report for the non-power-hungry device may be down to this (5 years, 10 years, basically the same: ballpark figure, remember ).

True, but I still think the ballpark figure of 10 is a bit on the optimistic side

Originally Posted by Hollow Man

My point was that most people aren't going to see a serious decline in battery life before they decide to stop using the device permanently. If they use the device all the time, the battery gets proper "exercise". If they use it sparingly, then even if there are deep discharges, it isn't enough to affect to affect life.

Nutshell: if someone notices an issue, by that time they're ripe for a new Kindle.

-HM

Yes and no. In case of my BeBook Mini, I really don't like it that the battery has degraded to such an extent, as there simply is no replacement for the reader. Nobody bothers to make a 5" reader anymore

On average though, yes, I think you're right. By the time a battery degrades so much it's no longer usable, there are so many so much better devices out there that you are happy your battery is gone and you have a good excuse to get a new one

[barryem]

I think the point that Amazon are not fools and that they may have done something to improve the overall lifetime of the battery is a good one. Amazon doesn't make things that don't last, as a rule. And yet I don't see what they might have done to help in this situation.

If it turns out I was wrong and people are still getting decent battery life from their Oasis a few years from now then that's a good thing and I'll find myself wishing I'd gotten one. It's just too much money to risk on something I have so little confidence in.

For you guys who have an Oasis and are enjoying it, I'm glad. Everything I've seen tells me that it's a nice device. I've mentioned this issue before to people who have gone ahead and bought one with the idea that they want it and it'll last as long as it lasts and that'll be okay. Seems reasonable to me as long as it's not my money.

Barry

[Atunah]

Originally Posted by barryem

I think the point that Amazon are not fools and that they may have done something to improve the overall lifetime of the battery is a good one. Amazon doesn't make things that don't last, as a rule. And yet I don't see what they might have done to help in this situation.

If it turns out I was wrong and people are still getting decent battery life from their Oasis a few years from now then that's a good thing and I'll find myself wishing I'd gotten one. It's just too much money to risk on something I have so little confidence in.

For you guys who have an Oasis and are enjoying it, I'm glad. Everything I've seen tells me that it's a nice device. I've mentioned this issue before to people who have gone ahead and bought one with the idea that they want it and it'll last as long as it lasts and that'll be okay. Seems reasonable to me as long as it's not my money.

Barry

I'll keep you updated on it each year. . Course, after a few years, I might have yet another kindle. Although I can't think of what they could improve on it.

The Voyage, which you have I think is a mighty fine device. I have one too and it still works fine. And if having buttons and the ergo design of the Oasis aren't important to you and others, there really wouldn't be a point I don't think to get the Oasis.

[Sweetpea]

Originally Posted by Atunah

I'll keep you updated on it each year. . Course, after a few years, I might have yet another kindle. Although I can't think of what they could improve on it.

The Voyage, which you have I think is a mighty fine device. I have one too and it still works fine. And if having buttons and the ergo design of the Oasis aren't important to you and others, there really wouldn't be a point I don't think to get the Oasis.

And that's why it's so good to have a choice! You can decide on the reader that fits your checklist best.

For me, I loved the form of the Oasis, but it had two major downsides: price and the fact that is a Kindle (never liked the software).

[NullNix]

Originally Posted by Atunah

The Voyage, which you have I think is a mighty fine device. I have one too and it still works fine. And if having buttons and the ergo design of the Oasis aren't important to you and others, there really wouldn't be a point I don't think to get the Oasis.

Quite. I'd have bought a Voyage if it hadn't been for the Oasis coming out and having all the new and shiny on it (and being ergonomically better, which matters to an RSIan like me).

[JSWolf]

Don't you always need a new one?