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#1 |
Wizard
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Karma: 429063498
Join Date: Aug 2014
Location: Mauritius
Device: Kindle Paperwhite 4
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Optimal time to recharge a Kindle PW4?
My kindle has taken a turn for the worse. I am thinking of getting a newer kindle but would like to know if I did wrong by charging the kindle everyday. The battery decreased by 9-10% by the end of the day. Now though, for the first time, it has gone down by 7 % without me reading from it. Therefore the title of my post.
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#2 |
Wizard
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Karma: 16307824
Join Date: Sep 2022
Device: Kobo Libra 2
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Yes, you're damaging the battery by doing that. Lithium-ion batteries dislike being fully charged or discharged. You're better off keeping the charge between 25 - 75% most of the time and only doing full charge and discharge cycles once every few months.
It's also possible that you've thrown off the battery calibration by charging it so much. Charge it to 100% and then don't charge it again until you get < 10% left, then repeat the process. It's possible that exercising the battery a few times will improve the situation, but having kept it at > 90% for so long, you've undoubtedly done some permanent damage to the battery. |
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#3 | |
Resident Curmudgeon
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Karma: 145864619
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3
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Quote:
You should only charge when the battery gets low or you know you need it charged (like going on vacation). Most eInk Readers do not need a daily charge. How long between charges depends on how much you read and and how much you plug into the computer. WiFi left on also uses battery. So keep the WiFi off until you need it. Last edited by JSWolf; 10-29-2022 at 06:47 PM. |
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#4 |
Grand Sorcerer
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Karma: 70766125
Join Date: Feb 2009
Device: Kobo Clara 2E
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I would give it a few more tries before jumping to any conclusions. Can kindles be rebooted?
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#5 |
Wizard
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Karma: 20102554
Join Date: Aug 2018
Location: Central Florida
Device: Oasis 3, PW 3 & 5, Fire HD 8 & 10
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Going down by 7% once isn't that big of a deal. Mine randomly do that also when not in use. There's no reason to charge it daily, but if that's the only sign, I doubt it's ruined.
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#6 |
Resident Curmudgeon
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Karma: 145864619
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Libra 2, Kobo Aura H2O, PRS-650, PRS-T1, nook STR, PW3
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@Luffy, don't charge everyday and see how long the battery lasts before it says it's low. That will tell you the condition of the battery.
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#7 | ||
Grand Sorcerer
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Karma: 103362673
Join Date: Apr 2011
Device: pb360
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Quote:
Quote:
But doing a recalibration as suggested above should be tried before coming to a conclusion regarding the results of a restart. Only if the battery meter has been recalibrated as suggested above. |
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#8 |
Wizard
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Karma: 429063498
Join Date: Aug 2014
Location: Mauritius
Device: Kindle Paperwhite 4
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BIG THANKS to EVERYONE for pointing out what was wrong! Thanks!
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#9 |
Grand Sorcerer
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Karma: 70766125
Join Date: Feb 2009
Device: Kobo Clara 2E
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#10 | |
Connoisseur
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Karma: 2492712
Join Date: Jun 2022
Location: Saratoga Springs, NY
Device: Kindle Paperwhite, Amazon Fire HD8 (2020)
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Quote:
Long press the power button until the screen flashes to the Amazon logo. Then sit back and wait for the magic to happen. |
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#11 |
Connoisseur
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Karma: 2492712
Join Date: Jun 2022
Location: Saratoga Springs, NY
Device: Kindle Paperwhite, Amazon Fire HD8 (2020)
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I agree with others that a Kindle shouldn't need charging every day. I read several hours a day, and I recharge when the battery level gets down to between 20-40%; my experience is that I have to recharge around once a week or thereabouts. I generally don't charge to 100%; the design of a Kindle makes it less convenient to know the actual charging state. Instead I charge until the LED turns green which is around 95%.
Incidentally, others have suggested that leaving the WiFi off will save battery. That's probably true. I leave WiFi on most of the time, but most of the time my Kindle is at home where it is continuously connected to WiFi. I know that cell phone batteries discharge more rapidly when you are out of cellular range, and I suspect a similar phenomenon applies to Kindles and WiFi. So I do put my Kindle in airplane mode if I'm going to take it away from home. I think its an oversimplification to say that lithium ion batteries don't like to be fully charged. What they don't like is elevated temperature, and fully charging a lithium ion battery to 100% can cause the temperature to rise unless the charging circuit is designed to taper the charging rate as the battery approaches full charge. Some smart phones are are designed to offer tapered charging, but they are also more expensive than a Kindle. You get what you pay for. Batteries are electrochemical devices, and elevated temperature causes changes in some of the chemicals used in a battery. So the other issue is that if the ambient temperature is elevated (say, in a desert environment), the battery won't last as long. Lithium ion batteries do display a 'wear out' characteristic that is related to the number of charge-recharge cycles; a cycle is defined as charging from 0% to 100%, so charging from 25% to 75% is half of a charging cycle. Amazon probably has a design target for the number of charge-recharge cycles a Kindle battery is expected to support, but they haven't made that information public. |
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#12 |
Wizard
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Karma: 16307824
Join Date: Sep 2022
Device: Kobo Libra 2
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Heat is only part of the problem. Lithium-ion batteries are also stressed when their voltage is too high (100% charged) for long periods of time, which causes the batteries to degrade faster. See here:
https://batteryuniversity.com/articl...ased-batteries The worst case scenario is storing the battery at 100% charge in a hot environment. Even though you're not using the battery at all, the capacity will rapidly decline. |
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#13 |
Still reading
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Karma: 105092227
Join Date: Jun 2017
Location: Ireland
Device: All 4 Kinds: epub eink, Kindle, android eink, NxtPaper
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Yes, storing at Lithium Ion at 33% to 66% approx is best in cool but above maybe 5 °C.
NiCd and NiMH are stored best discharged. Lead Acid is stored best 100% charged (or 100% charged/manufactured and dry without acid which gives decades of shelf life). |
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#14 | |
Guru
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Karma: 15576314
Join Date: Jan 2013
Location: Ely, Cambridgeshire, UK
Device: Kindle Oasis 3, Kindle Oasis 1
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Quote:
So there is little harm in fully charging a Kindle: it's just a bit of a waste of time if it's already almost charged. Most battery aging (as with almost all li-ion batteries with a competent charging circuit in the loop) is going to be due to oxidation, and you can't really avoid that as long as you like living on a planet where you can breathe. |
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#15 |
Wizard
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Karma: 16307824
Join Date: Sep 2022
Device: Kobo Libra 2
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Interesting. I knew electric cars would lie about the current charge level, but I didn't know a Kindle would.
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