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How to prolong lithium based batteries

batteryuniversity.com

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Re: How to prolong lithium based batteries

#81

Post by cubefox »

freehorse wrote: post #53
cubefox wrote: post #49

I think all systems that allow for fast charging should, after plugging in, ask: "Do a slow charge instead?" and perhaps: "Only charge to 80%?". These could be two check boxes that are unchecked by default. Maybe you could change the default in the settings. Anyway, the way this is currently solved e.g. in Android is clearly suboptimal. You can only configure charging in the settings, but obviously it depends on your…

I actually have a couple of chargers that just do _exactly_ 5V/1A for this reason.

Yeah, but a software solution would be better and actually easy to implement.

Re: How to prolong lithium based batteries

#82

Post by clearleaf »

pkulak wrote: post #77
mnw21cam wrote: post #62

I have had my phone for 4.5 years. I charge it every night to 80% - I have Accubattery installed, so it pings to tell me to unplug it, and it also does a fairly decent job of measuring the capacity. I charge on a fast charger (10W) instead of the super-fast charger (18W) because that keeps the temperature from rising too much. I use the phone a fair amount, so I'm usually charging from around 50%. Therefore, the batt…

I just use the hell out of my phone battery and pay 50 bucks every 3 years to replace it.

Me too except my first phone is the only one where I had to replace the battery. My 5 year old phone still lasts the whole day without going through any of this rigmarole. It's mostly superstition and the parts that aren't are such a wash that they aren't worth worrying about. Just look at these people trying to reach an agreement on whether you should stop charging at 80% or not. Your gadgets should work for you not the other way around.

Re: How to prolong lithium based batteries

#83

Post by Filligree »

fy20 wrote: post #73
speedgoose wrote: post #14

Earlier quoted context omitted.

I was told that LFP is difficult because the battery management system (BMS) cannot reliably guess the state of charge using the voltage. The voltage is a mess on LFP. Even though a lower voltage prolongs the battery, you have to charge to 100% regularly to help the BMS. Thankfully the LFP chemistry doesn’t seem to mind high state of charge as much. As a popular source, Tesla recommends to daily charge the LFP batter…

The 100% charge thing is also for balancing, as most BMSs are pretty dumb and only use passive balancing. When an individual cell reaches a set voltage, a resistor is turned on which bleeds the excess power preventing that cell from overcharging. When the pack reaches 100% theoretically every cell should then be at the same voltage.

If that's the case, then if you don't regularly charge to 100% you can end up depleting any cell that's out of balance. Good to know.

Re: How to prolong lithium based batteries

#84

Post by Kirby64 »

andruby wrote: post #50
speedgoose wrote: post #14

Earlier quoted context omitted.

I was told that LFP is difficult because the battery management system (BMS) cannot reliably guess the state of charge using the voltage. The voltage is a mess on LFP. Even though a lower voltage prolongs the battery, you have to charge to 100% regularly to help the BMS. Thankfully the LFP chemistry doesn’t seem to mind high state of charge as much. As a popular source, Tesla recommends to daily charge the LFP batter…

> The voltage is a mess on LFP That's a weird statement. The voltage curve for LFP [0] is just a lot flatter. That's nice for your electronics, but makes it hard to estimate state of charge based on the voltage alone. So the BMS needs to keep track of total energy used to calculate state-of-charge. [0] https://www.jackery.com/blogs/knowledge/ultimate-guide-to-li...

The problem is that total energy used is never fully accurate so coulomb counting can only be so good. Top and bottom balancing is needed to reset the algorithms, otherwise state of charge is largely a guess especially over time.

Re: How to prolong lithium based batteries

#85

Post by SubiculumCode »

ydant wrote: post #65
SubiculumCode wrote: post #59

Earlier quoted context omitted.

ill have to check: its a 2023 bolt euv

Bolt will cool itself, but it does so more aggressively when plugged in (even if not actively charging). I always leave our EVs plugged in when it's over about 80F and below freezing because of that. My 2021 is complaining loudly (running the cooling system) about the heat-wave today.

Thanks for that info. I'll definitely keep it plugged in then.

Re: How to prolong lithium based batteries

#86

Post by callalex »

cubefox wrote: post #49

I think all systems that allow for fast charging should, after plugging in, ask: "Do a slow charge instead?" and perhaps: "Only charge to 80%?". These could be two check boxes that are unchecked by default. Maybe you could change the default in the settings. Anyway, the way this is currently solved e.g. in Android is clearly suboptimal. You can only configure charging in the settings, but obviously it depends on your…

Every Apple device (even headphones!) does this by inferring your schedule and charging to 100% just in time or just never if for example you charge your watch every night but only use half the battery. I just wish it was slightly less automatic because it definitely gets tripped up by my occasional insomnia.

Re: How to prolong lithium based batteries

#87

Post by cubefox »

callalex wrote: post #86
cubefox wrote: post #49

I think all systems that allow for fast charging should, after plugging in, ask: "Do a slow charge instead?" and perhaps: "Only charge to 80%?". These could be two check boxes that are unchecked by default. Maybe you could change the default in the settings. Anyway, the way this is currently solved e.g. in Android is clearly suboptimal. You can only configure charging in the settings, but obviously it depends on your…

Every Apple device (even headphones!) does this by inferring your schedule and charging to 100% just in time or just never if for example you charge your watch every night but only use half the battery. I just wish it was slightly less automatic because it definitely gets tripped up by my occasional insomnia.

That's something else because it assumes a stable schedule, while I proposed dynamic options that can be activated once the charger is plugged in. Just let people optionally choose how far and how fast they want to charge this time. The default can be as "smart" as it already is.

Re: How to prolong lithium based batteries

#88

Post by attentive »

mnw21cam wrote: post #62

I have had my phone for 4.5 years. I charge it every night to 80% - I have Accubattery installed, so it pings to tell me to unplug it, and it also does a fairly decent job of measuring the capacity. I charge on a fast charger (10W) instead of the super-fast charger (18W) because that keeps the temperature from rising too much. I use the phone a fair amount, so I'm usually charging from around 50%. Therefore, the batt…

I have a smart plug configured to power plugged into it charger for 40min or so during the night. It takes it to ~80-85% and it's automatic.

Re: How to prolong lithium based batteries

#89

Post by ece »

Charging at 1C or less on phones would mean 20W on a 5000mAh battery. For laptops it would be 100W maximum, probably 65W or 45W for most laptops. All the Dell laptops I have allow me to set a low percentage and high percentage, and I have the high set to 55% on laptops I use primarily plugged in, and 80-90% on more mobile laptops. Now if only Pixel phones and ereaders/watches/battery banks also allow me to have such control over how much to charge.

Would be ideal to have LFP batteries and such control, but that will take a while.

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