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Charging a lithium battery to 80% only?

electronics.stackexchange.com

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Re: Charging a lithium battery to 80% only?

#61

As a consumer do I have to worry about this or will BMS handle things? My kid runs his 3DS until it shuts off and I was wondering what impact that kind of behaviour might have.

I wouldn’t expend any energy worrying about it. It’s meant to shut off before causing any damage. And even if you could slightly extend the life by babying the battery, who cares, you can trivially replace the 3DS battery for cheap.

Re: Charging a lithium battery to 80% only?

#62
One of my pet peeves is how people get so dismissive about limiting their battery charge. People will even get defensive, as if it is a personal attack or something. Empirical evidence has shown time and time again that it is a-matter-of-fact that stopping charge at 80% will prolong a lithium-ion battery. [1][2][3]

I mean, it’s one thing to be believe that it is “too inconvenient” or that “life’s too short to micromanage my phone battery”, and another to blatantly spread lies that stopping charge at 80% is a “myth” with no benefit. And maybe that “micromanagement” argument was true 5 years ago, but nowadays nearly every device can automatically limit charge levels, e.g.:

iPhone 15 and above

iPhone 14 and below with a smart-plug[4]

Most Samsung phones/tablets

Sony phones/tablets

Any rooted Android

Any decent EV

Windows: Asus, Dell, HP, Lenovo, and Microsoft laptops

MacOS through AlDente[5]

Linux: TLP for most manufacturers[6]

And honestly if your device can’t automatically limit charge, I concede it probably isn’t worth the micromanagement. But those kinds of devices have small, cheap, and easy to replace batteries anyway.

It’s a heck of a lot different to drive to the Apple Store and spend $250 for a MacBook battery versus the $30 battery and half hour of work for Nintendo Switch.

[1] https://batteryuniversity.com/article/bu-808-how-to-prolong-...

[2] https://accubattery.zendesk.com/hc/en-us/sections/202397985-...

[3] https://www.sciencedirect.com/science/article/pii/S235248471...

[4] https://forums.macrumors.com/threads/how-to-set-an-automatio...

[5]https://github.com/AppHouseKitchen/AlDente-Charge-Limiter

[6] https://linrunner.de/tlp/settings/bc-vendors.html

Re: Charging a lithium battery to 80% only?

#63
post #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.

I'm not so sure it would result in less waste. Apple will replace the batteries cheaply and recycle them; how many user-replaced batteries will go in the trash? How many extra batteries will people buy and never use, or replace their batteries before they actually need to?

Re: Charging a lithium battery to 80% only?

#64

Earlier quoted context omitted.

> ”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…

What happens if you actually do fully drain an EV on the road? How do you recover from that situation? Normally you’d just have to get a container of fuel delivered to you.

Most likely you get towed to the nearest charger on a flat-bed truck. But portable chargers (with batteries or diesel generators) on the back of trucks or vans also exist.

Some EVs also support power output (V2x) from their charge ports, allowing you to charge up one vehicle from another.

Re: Charging a lithium battery to 80% only?

#65

Earlier quoted context omitted.

I've been trying a similar experiment for several years now. I have a four year old iPhone, and for most of its life, the battery level has been kept between 30% and 70%. Settings => Battery => Battery Health and Charging says that the maximum capacity is 91%. No idea whether that's better or worse than average, but I mention it so others can compare. I can say that this is the first time I've tried this experiment,…

Did you have an automated way to do that?

I wish I did but I haven't found one yet. I'm at my desk a lot, and that's usually when I charge it. I mostly use an old, low-current charger (originally for a bluetooth headset) so it charges slowly, about 5% per hour.

Re: Charging a lithium battery to 80% only?

#66

Earlier quoted context omitted.

Cheap for the wallet, but not the biosphere. Unless you mean to imply that people would get new phones less frequently?

How is that all that damaging? I’m sure those batteries are recycled in basically all cases and yes, I’d expect battery replacement does indeed forestall replacement for many phones.

The most common processes for recycling lithium ion and lithium polymer batteries are not environmentally friendly. They consume a lot of water and energy and produce toxic byproducts the require further processing and energy to be rendered safe.

https://pubs.acs.org/doi/10.1021/acsenergylett.1c02602

Re: Charging a lithium battery to 80% only?

#67
The battery in my pixel 4xl failed two times under warranty and then a third where googles service provider wouldn't do it again for me. (The ribbon connector is actually what fails).

So I went to Amazon and bought a $14 kit that came with a battery AND tools. Did it myself in 15 minutes. (Whereas the UBreakIfix vendor took like 2 hours of my time between dropoff and pickup).

The Amazon battery has lasted longer than 3 Google official batteries did. Even so, I no longer worry about batteries when all these cheap kits and instructions exist.

Re: Charging a lithium battery to 80% only?

#68
post #55

Does anyone know how limited charging works with balancing? As I understand balancing only happens when batteries reach their full capacity. A bit of background: Batteries are made up of cells which have ever so slightly different voltages. If you have three 3.7v cells in series to make a 9.2V some cells will be 3.68V and another could be 3.72V. This is bad, because when you charge the battery it is charged as a whol…

1. Balancing does not change the internal impedance of cells with different aging characteristics. You will be constrained by the weakest cell behaving more like a crude resister in the pack over time.

2. Balancing does ensure the capacity of all cells is maximized, but does not match each discharge characteristic under load.

Thus, the method can improve cell life under shallow changing, but can't atop unbalanced loading with random cell impedance mismatch.

There are good chargers and special meters that can help match a set of cells.

Best of luck =)

Re: Charging a lithium battery to 80% only?

#70

Earlier 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.

Yeah but then you have to buy an iPhone.

That's not snark. I want things from my phone that an iPhone can't give me.

The battery replacement ecosystem in Android land is pretty dismal.

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