Charging a Li-Ion battery

[Sussudio]

I'm sure there are several people here knowledgeable in electronics that can help me with this, as every time I've searched the internet I find conflicting answers to my question: what is the proper way to charge a lithium ion battery to preserve it as long as possible (in this case i'm referring to my laptop battery)?

[Rob71]

I've only had mine for a few months. But I keep my battery plugged in and have my alarm sound at 30%. I was told to do partial discharge/charge cycles and every 20-30 charges do a full discharge(5-10%). If you use the power cord for long periods you should store the battery with a 40% charge. Don't know how accurate that is, but a few different people have told me basically the same thing.

[Sussudio]

Originally Posted by Rob71

I've only had mine for a few months. But I keep my battery plugged in and have my alarm sound at 30%. I was told to do partial discharge/charge cycles and every 20-30 charges do a full discharge(5-10%). If you use the power cord for long periods you should store the battery with a 40% charge. Don't know how accurate that is, but a few different people have told me basically the same thing.

ive heard that too. ive been always charging my battery when it gets to about 5% and then do a full charge back to 100. since i dont use the battery much i generally leave it out but its been at around 100 (although i realize it slowly discharges). i'll start doing it around 40% though from now on. any idea why that seems to be "the magic number?"

[Rob71]

Originally Posted by Sussudio

ive heard that too. ive been always charging my battery when it gets to about 5% and then do a full charge back to 100. since i dont use the battery much i generally leave it out but its been at around 100 (although i realize it slowly discharges). i'll start doing it around 40% though from now on. any idea why that seems to be "the magic number?"

I don't know. But when I bought my netbook pretty much all the sites said basically the same thing. Maybe they all read the same blog.

[mikejet]

Li-Ion batteries are unlike the old Ni-Cad rechargables in that they do not suffer from memory problems. It is not necessary for you to fully discharge them and is actually harmful to do so too many times.

Charge them as often as possible.

The weird things you learn when you used to work at Radio Shack.

[Sussudio]

Originally Posted by mikejet

Li-Ion batteries are unlike the old Ni-Cad rechargables in that they do not suffer from memory problems. It is not necessary for you to fully discharge them and is actually harmful to do so too many times.

Charge them as often as possible.

The weird things you learn when you used to work at Radio Shack.

ok, but i assume it's not good to just leave it in all the time if my laptop is going to stay plugged in right? i did that with a previous laptop and after a year or so the battery seemed to discharge rather quickly when used. i have friends whose laptop batteries are still going strong well into their 3rd year of use.

[phlydude]

I have a laptop with a Li-Ion battery for nearly 4.5 years now - the damn power charging port went bad before my battery and I pretty much leave the thing plugged in all the time.

Sure, a couple times every 2-3 months, letting the battery discharge is good but Li-Ion batteries are much more forgiving.