Best way to charge Li-on batteries?

[LEDninja]

NiCd/NiMH seem to like full discharge.
Lead acid/Recharable alkalines (Renewal,Pure Energy) like to stay topped up at all times?
What about Li-ons? Constantly topping them up or letting them do a full discharge?

 

[DM51]

You should never let Li-Ions fully discharge. Aim to keep them between 3.5v - 4.2v.

 

[ltiu]

Slightly off topic.

Li-on batteries are used frequently in cell phones. I always hear people say that you should use up your cell phone batteries till it is almost out, before you re-charge it.

Is this true?

OR

Is this "still" true?

 

[DM51]

Modern cell phone batts are mostly Li-Po, which should be treated the same as Li-Ion. So in other words, no, what you have been told is not true, but the phone will have a pretty foolproof protection circuit to prevent over-discharge anyway.

 

[Tritium]

Slightly off topic.

Li-on batteries are used frequently in cell phones. I always hear people say that you should use up your cell phone batteries till it is almost out, before you re-charge it.

Is this true?

OR

Is this "still" true?

It was only true when Cell Phones used NiMh. No longer true with Lithium Ion.

Thurmond

 

[OhMyGosh]

I have heard that lithium-ion likes to be stored at around 1/2 charge (40%). As far as running them down I don't think it makes a big difference - just don't let the voltage get to low.

 

[DM51]

I have heard that lithium-ion likes to be stored at around 1/2 charge (40%).

You can store Li-Ions at up to 4.1v (~90%) without damaging them.

As far as running them down I don't think it makes a big difference - just don't let the voltage get to low.

Aim not to go below a voltage of 3.5v at rest.