I'm in the "flashlight nerd" gang, and I've learned to store my long-term storage li-on batteries at near 50% capacity to extend their life tremendously. I've also implemented this strategy with my portable chargers, and they've lasted for years now at full capacity still.
Charging a lithium battery to 80% only?
31–40 of 362 posts
Re: Charging a lithium battery to 80% only?
#32I 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.
BMW i3 does that, kinda. I checked the raw data against the claimed battery size, and the in-car 0-100% was 20-80% of the battery.
My new Renault Megane E-tech does not do this. Instead it has an option to limit charging to a given percentage (if you set it to 100% it'll ask if it's just next charge) and the manual states that if you have less than 15km range the car might switch off at any moment without notice...
Let's just say I was mildly surprised about the latter.
Both cars had battery guarantees though, the Megane's is minimum 80% SOH after 8 years or 160000 km, with no reservations against charging to 100%.
Re: Charging a lithium battery to 80% only?
#33I'm in the "flashlight nerd" gang, and I've learned to store my long-term storage li-on batteries at near 50% capacity to extend their life tremendously. I've also implemented this strategy with my portable chargers, and they've lasted for years now at full capacity still.
Full half capacity?
Re: Charging a lithium battery to 80% only?
#34I'm in the "flashlight nerd" gang, and I've learned to store my long-term storage li-on batteries at near 50% capacity to extend their life tremendously. I've also implemented this strategy with my portable chargers, and they've lasted for years now at full capacity still.
Full half capacity?
The total capacity, meaning the battery's original mAh capacity.
Re: Charging a lithium battery to 80% only?
#35"Adaptive Charging" is the answer to this problem no?
My phone lowers the rate of charging so it's only at 100% by the time you wake up.
Even just making it easier to replace the battery ("right to repair") would mitigate this.
Re: Charging a lithium battery to 80% only?
#36I 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 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.”
They already do! In most EVs, 0% is not really zero: you can typically drive another 20-40 miles before it finally dies.
Most EVs will easily have a battery life of 200K miles, with some capacity degradation. Active battery management such as limiting the max charge is more about preserving the battery life beyond this, and reducing degradation.
And all of this becomes less necessary with LFP battery chemistry, which is leas fussy about charge levels and less susceptible to degradation.
Re: Charging a lithium battery to 80% only?
#37Earlier quoted context omitted.
> Those are replaceable and cheap to replace every couple of years. If you specifically seek out devices with cheap replaceable batteries, sure. But this isn't the case with a lot of devices.
Replacing an iPhone battery is cheap, especially compared to replacing the whole phone: at the Apple Store it’s either $99, $69 or $49 and I’ve had other stores do it for like $40. That’s not too bad for a once every couple years cost.
Cheap for the wallet, but not the biosphere. Unless you mean to imply that people would get new phones less frequently?
Re: Charging a lithium battery to 80% only?
#38I wish they would label it so that it shows 100% charge when it's actually charged 80%, and then give an option to 'overcharge' a configurable amount till 125% (the current 100%). That way it will make people aware that they are reducing the battery life by overcharging, and be picky when they overcharge. But this won't happen because reduced battery life is a big direct and indirect(by reducing performance like Appl…
I'm pretty sure most (all?) manufacturers already do (the first part of) this. 100% can't be the point at which the battery literally stops taking new charge - if you did that they'd catch fire all the time. It's just that the manufacturers idea of what "100%" should be generally skews more towards the immediate battery life end of the tradeoff, whereas some users prefer to have "100%" closer to the maximizing long t…
Almost everyone caps below max voltage, but a toggle between small margin and big margin is a lot less common. And if you have to reboot into the bios, it only half counts.
Re: Charging a lithium battery to 80% only?
#39Earlier quoted context omitted.
Almost nobody cares about saving batteries. Those are replaceable and cheap to replace every couple of years. Innovating more battery life and leaving 20% battery life on the table sounds extremely pointless for what costs 20-30$ a year but lets you use the device all day instead of just shutting before the end of the day.
> Those are replaceable and cheap to replace every couple of years. If you specifically seek out devices with cheap replaceable batteries, sure. But this isn't the case with a lot of devices.
The cost to replace the battery on iPhones, which most people would consider to be “difficult to replace” is only $100 directly from Apple. Really seems like paying an extra $100 every 2-3 years is a decent deal for something that has 20% more battery.
Re: Charging a lithium battery to 80% only?
#40I'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…
> So I just leave them plugged in
Isn't that exactly why you want a device that can self-limit? It doesn't need to lie.