How to prolong lithium based batteries

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 battery has had ~1600 cycles of around 30%, or 480 full cycles equivalent. The design capacity of the battery is 4000mAh, and Accubattery tells me it currently stores 3460mAh, which is 87% of the design capacity.

I therefore approve and recommend the above strategy for treating the battery to make it last longer. I also recommend Accubattery - it seems to do the job fairly well.

I’m not a battery expert but some coworkers from the battery lab at work are, and they say that charging more often is better than doing big cycles. On most chemistries.

In more concrete terms, it’s better to keep the state of charge between for example 60 to 30% compared to for example 80% to 15%. Big cycles like 100% to 5% are the most damaging over time.

Like making anything last, don't operate at the limits of its envelope.

   * Limit max temperatures
   * Reduce maximum currents in and out
   * For lithium batteries, limit peak charge to 3.92V, do *not* charge to over 4.1V or 30degC

I can't find the specific research study, but NASA did a study that last I read was going on for over 30 years with a neglible drop in capacity by only operating in the flat portion of the charge/discharge curve. The result is that properly speccd battery packs (probably > 1.5x most battery packs) can last indefinitely. For my cordless tools, I get the largest modules I can (5Ah). I have a single slim 2Ah module for fitting in tight spots.

*edit, when using a cheap intermittent high current device, like a hand vacuum, apply a duty cycle, like 30 seconds on, 10-30 seconds off to prevent the internal battery pack from getting too hot. These kinds of consumer goods have the smallest battery pack that will outlast the warranty.

I really wish battery charge profiles were codified in QR codes on the modules themselves (besides existing on an I2C bus).

Short-Course on Lithium Ion Batteries https://ntrs.nasa.gov/api/citations/20190030819/downloads/20...

battery aging dataset (appears dead) https://c3.ndc.nasa.gov/dashlink/resources/133/

https://www.nasa.gov/wp-content/uploads/2021/10/3-nasa_batte...

https://ntrs.nasa.gov/api/citations/19990032333/downloads/19...

Some tools I use to actually follow this advice on various devices: I use Chargie devices (chargie.org - no affiliation) to control maximum charge level, and set thermal limits on smartphones and other small devices that can't limit charge internally with software. I also use a Peltier cooled phone holder and charger in the car (about $50 on Amazon), so it keeps the phone cool when charging and processing hard during navigation, and in direct sunlight. On Macbooks I use the free Al Dente app which lets me manage charge level. When I owned an e-Golf EV, I was able to set charge limits through the VW Car-Net app.

I wish I could find this information for LFP batteries. There’s a lot out there, but it’s all mixed with advice for LiPo; I can’t find anything I trust to tell me the optimal voltages for maximum lifetime.

Two unconventional things I do to improve my iPhone's battery health (which follow this article's findings): 1) Don't use a case - Otherwise, you are literally wrapping your phone in a rubber insulator 24/7, increasing its overall temperature. 2) Don't charge at night - Turn off your phone at night. Instead, charge it during the day when you're at your desk. This reduces the number of cycles over years (because your phone is continually draining/recharging all night even when you aren't using it)

Plugged-in phones should use power directly instead of passing through and degrading the battery.

1. It’s ok to keep laptop plugged in, even at 100% battery

2. Keep temperature as low as possible, maintain airflow

3. Avoid fast chargers

I've been using ACCA[0] to set limits on battery charging on Android devices for years. Note that it requires root.

ACCA can limit charge percentage, allowing the device to operate plugged in without charging beyond a certain point. It can also pause charging when the temperature exceeds a threshold, limit the charge rate, and several other tweaks to charging behavior. By default, I use a charge limit of 60% and a charge rate of 500 mA, increasing those when needed.

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

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.

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 current situation whether you want to use your device immediately and need a full charge.

All Galaxy phones have a configuration to limit the charge to 85%

Note that in most battery chemistries, the degradation floors at around 80% whatever you do.

These advices are to get to that 80% slower. If you are fine with having 80% in like 2 years instead of 10 years, you don’t have to really limit yourself.

A better way will be manufactures to advertised 100% as current 80% and allows you to boost you to 120%.

I've been doing 80% >> 45% for a while on a 14 pro max....on a best effort manual basis.

Appears to be working...I'm on 93% battery health today while googling suggests others where hitting <90% in mid 2023 already.

So unscientifically it does seem to matter, though whether it is worth the hassle is another question

The article mentioned heat. I park my ev in the sun in CA. Definitely hotter than 86 degrees. Does the car protect the battery somehow with cooling, or do I need to find shade asap.

Every time I hear about that stuff, I see this website listed as source. What is their source?