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Charging a lithium battery to 80% only?

electronics.stackexchange.com

11–20 of 362 posts

Re: Charging a lithium battery to 80% only?

#11
I kinda wish my EV would just set the apparent 0% and 100% points at a level that guaranteed X cycles, where X corresponds to perhaps 200K miles. As capacity and fast charging infrastructure improves, it'll be less important for me to access the top 20% of the battery just to make a road trip feasible.

Hell, I'm okay with it just being a lie that I can control. Let me choose those points.

Re: Charging a lithium battery to 80% only?

#12
I've been using ACCA[0] for years to limit charge on my phone, usually to 60%, but higher when needed. I also limit the charging speed most of the time.

It performs like new despite the phone being over three years old. I'm determined to keep it usable as long as I can because I prefer its size and analog headphone jack over what's available now. Actually replacing the battery, however looks like a big hassle, so I'm determined to put that off for years.

[0] https://f-droid.org/packages/mattecarra.accapp/

Re: Charging a lithium battery to 80% only?

#13
post #10

I recently bought a Pixel phone after having Samsung for a few years. Immediately the one thing that annoyed me was the lack for both limiting charge as well as enforcing slow charging. Both not only are useful for long term battery life but also, since I'm an occasional thruhiker (right now on my way to Mexico along The Continental Divide Trail), they make better use of my power bank. Without rooting the device thes…

By default my Pixel will slow charge when I set it down at the end of the day and be at 100% when my alarm goes off in the morning.

Re: Charging a lithium battery to 80% only?

#14
I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge.

But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Apple does with old iPhones) driver of phone upgrades.

Re: Charging a lithium battery to 80% only?

#15
post #12

I've been using ACCA[0] for years to limit charge on my phone, usually to 60%, but higher when needed. I also limit the charging speed most of the time. It performs like new despite the phone being over three years old. I'm determined to keep it usable as long as I can because I prefer its size and analog headphone jack over what's available now. Actually replacing the battery, however looks like a big hassle, so I'm…

If phones with easily replaceable batteries arrive due to legislation, it would be one major win, less waste and more peace of mind.

Re: Charging a lithium battery to 80% only?

#16
post #3

I've given up trying. If a device is willing to lie to me and only charge to 80% while saying it's charged, great, but all of this "try to stay in a range" logic flies in the face of reality. Every device I use besides my cell phone, Nintendo Switch, and Nintendo 3DS has atrocious power drain when not in use. OS does not matter. Windows laptop, Linux laptop, ChromeOS laptop, Android Tablet, Amazon Tablet, you name it…

I just picked up my 2017 iPad Pro. It was last charged Nov 15. Been sitting by the bed mostly unused since. Currently at 80% charge. I haven’t experienced what you’re describing on an Apple device since they switched the laptops away from Intel chips.

In my experience, the OS does matter. I can’t believe how bad the rest of the industry is at this. Amazon’s Kindle line is incredible at this IME, but those are pretty atypical devices.

Screenshot from said iPad’s battery screen: https://postimg.cc/xcHpy5Sr

Re: Charging a lithium battery to 80% only?

#18

I kinda wish my EV would just set the apparent 0% and 100% points at a level that guaranteed X cycles, where X corresponds to perhaps 200K miles. As capacity and fast charging infrastructure improves, it'll be less important for me to access the top 20% of the battery just to make a road trip feasible. Hell, I'm okay with it just being a lie that I can control. Let me choose those points.

I find it a lot easier to keep my EV between 20 and 80% than my cell phone. Just plug in whenever you come home and set your top charge to 80%.

Re: Charging a lithium battery to 80% only?

#19
The rule of thumb is you roughly double cycle life for every 0.1v lower you go (approx. 10% of charge).

I would only restrict the full charge level of you never need the full charge available anyway. Eg. I only use about 60% of my phone's battery, so I can comfortably restrict it to 85% and have plenty of leeway to avoid running out. If there's a decent chance you need the full battery, just use the full battery.

Also consider how long you expect to keep a device. A couple of years of daily charging is 700 cycles, so worth considering preserving battery lifetime if it suits you.

Re: Charging a lithium battery to 80% only?

#20

I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge. But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Appl…

Top charge in a lithium battery is very arbitrary. Most batteries can tolerate going higher than the specified 4.2v, up to 4.3 or 4.35v - but the cycle life degradation is not worth the extra capacity.
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