rolf wrote@yasamoka if 40% is the optimal charge for preserving the battery lifespan, could they not be software that keeps the battery at this level even when your laptop is plugged in?
Ideally, lithium ion batteries should not be able to overcharge, since it's dangerous. Supposedly, they have built-in circuits which shut off the current to the battery once it's reading 100% (note that this can be off, as I said). Now if you were going to limit charging to 40%, then you would need to throw off the gauge to read 100% and the battery level to actually be 40% (calibrate gauge by full discharge and recharge, measure voltage at 100%, measure voltage at 40%), which is quite tough since the battery will not shut off when it reaches 0%, but may shut off at a much higher APPARENT level, which means the system would shut down without warning, and would require close monitoring. This is also damaging to the battery, except if you manually shut it off at let's say 5-10% ACTUAL level (again, measure voltage at 5-10%).
Software does not interfere with battery operation. It merely reads the information the battery reports, that which can definitely be off. According to my knowledge, REGULAR lithium batteries cannot be calibrated nor manipulated by software.
