If we’re talking long term storage the. 3.7 volts is the optimum. What that’ll correspond to for the Framework battery is anyone’s guess (unless the EC exposes the cell voltage? I haven’t got mine yet)
But I’d be shocked if the difference in degradation between storing at 40% or 50% is bigger than the degredation from the heat from the CPU.
Honestly, it’s not something I’ll ever worry about. I’ll probably set the charge cap to 80% for most of the time, charge it up before trips/days out, and just I’ve with any degredation until the battery no longer provides a useable amount of life, after which I’ll replace it and recycle the old one to be made into new fresh batteries.
Yes lithium-ion cells can be recycled, and with their prevailance in electronics and Electric Vehicles becoming mainstream it’s going to go from uneconomical to booming industry. After all, a mound of dead cells is basically just a very rich ore waiting to be refined…
The mainboard can run without the battery, but only if the power supply can supply at least 100W. And a recent bios version (I think older versions don’t work without the battery)
There is a bios option to soft disconnect the battery for cases where it’s left plugged in, but reports are the option switches off if mains power is disconnected and would need to be manually re-enabled. Battery Disconnect Usage
Ignore the 2C curve. This significant drop in voltage is because the battery is terrible.
As we can see from this 2Ah cell, the voltage drops sharply during the first 300mAh as well as the final 300mAh. The other thing to note is that the flatter the curve, the less the battery is stressed reaching that point (since it can release a lot of charge before losing voltage). So ideally you want the battery to never exceed 3.95V nor drop below 3.68V.
However, because we want to squeeze as much capacity out of every cell, we charge them up to 4.2V. We still define the “empty batt” line around the 3.7/3.6V mark, since we all agree that going below 3.5V is risky. This mean that keeping the battery between 50% (roughly 3.75V) and 75% (roughly 3.85V) mark. You can dip low to 40% but watch out for over discharge (since the battery self discharges ever so slightly)
Speaking of overdischarge cells.
Some time ago I have found a rechargeable LED light. It have a 400mAh soft-pack (silver plastic pouch) Lithium battery in it. When I found it, the battery has ballooned(puffed) like crazy, reading about 2 volts.
I want to get this battery out of misery (since I wanted to use this light), so I unplugged it from the light and plugged into my charger. After about an hour (of charging), I came back and noticed the battery have shrunk down, with only slight bulges on the sides. A few hours later it became a flat slab, voltage reading a healthy 3.94 (or so).
Some time later I decided to use that cell to power a broken Palm V. Because the Palm V have no internal charging circuit the battery voltage is exposed on the connector (which I can solder to). The internal battery is completely dead (and I cannot remove it), so I just soldered this cell to it and taped it to the back. However, I forgot to charge it and in about a week I found the battery puffed up again and palm V not waking up. so I charge it up again, and it shrunk down again. Several times this happened. It always shrunk down to its original size.
Some background knowledge. This “gas” that was released is hydrogen gas. It is released because of incomplete chemical reactions inside the cell as the voltage goes down. Typically, this is accompanied by other harmful buildups like lithium oxidize on the battery leads, just like in lead-acid car batteries with the solution forming crystals on the plates. And also, just like car batteries this process is somewhat reversible.
And so to see a cell magically un-puff itself (remember, a puffed cell is supposed to have suffered permanent damage) is like witnessing actual magic.
There are two other cases with Lithium cells puffing. One of which happened in my Fujitsu UH 554 laptop battery pack (a 4S). The laptop very slightly overdischarged, and one of the cells (among the four) puffed so badly it lift the touchpad. It look like a literal balloon. I tried to charge the laptop (which worked), but that cell refuse to take charge. It sat at 2.4V, before I decided to give up, dismantle the pack, and tossed that puffed cell away (hazardous material bin). I don’t want a chemical fire in my house.
The other three 400mAh cells are pretty comfortable. One of them is used on my PSP where it attaches to an original PSP 1200mAh pack (with the old li-ion removed) and gave it battery life for over a day, before dropping below 3.6V and trigger the battery protection circuit. The other two are around 3.8-4.0V and is just sitting on the bookshelf. Perhaps I should notify my parents to take care of the PSP (and another laptop) so the cells are in good condition.
Tip: Check all of your Li-ion at least once every year. Make sure they are not going to explode and start chemical fires. For internal batteries, as long as the device can power up (even if 1%) it is good, however to keep it in a comfort zone you might want to charge it up. To, like, 50%.
Ni-Mh (and older cell chemistry) tend to not be as delicate, but they don’t hold charge very well and leaks (instead of violently explode) toxic chemicals instead, because no special efforts are made to make them more safe.
If it heats up and the pressure of the contained gases increases, it could rupture the casing/bag and if the hot hydrogen and battery electrolyte get exposed to air, you will get an extremely hot fire you may not be able to extinguish.
Could be good, an extra indication that you should address the situation now. But if safety engineering in my day job has taught me anything, it’s that you don’t want to rely on electronic components or software for personal safety. Safety should be intrinsic to the design.
The fact that batteries swell up, containing the hydrogen, is actually a good thing and speaks to the safety features built into current lithium ion batteries. But you’d better hope that the bag holds! It’s under enormous pressure trying to contain flammable/explosive gas.
Just look up “battery discharge curve”. There is plenty of these done by labs from all over the world (some are included in certain battery specification page too) with different cells and sort. All typical Li-ion/LiPo will demonstrate this curve.
Bee has said you can still apply here. The team of community moderators are doing their best to keep the forum clean, but I also know they work on the principle of “try not to get involved if you don’t HAVE to”.
I’m running a batch for i71165G7, 64GB RAM, Crucial P5 Plus 2TB SSD on Windows 11 Pro, with BIOS 3.07 and I am showing the following from the Windows battery report. I have limited the charge to 80% in the BIOS since that feature has become available it is plugged in most of the time. ~11% drop in battery capacity seems a bit excessive for a 1-year-old battery.
Thanks, I will take a look at the links. It would be nice if they were able to get a battery with higher density, however on the upside it only takes 3 minutes to pop in a new battery. Sure beats my old Surface Pro 4 for repairability. LOL