Best rechargeable battery for the U2

I know this has been discussed but since the search feature isn't working I can't find it. Whats the best rechargeable battery for the U2. I know the Pila 168a fits but it's protected and I thought I read unprotected is the way to go since you don't need a protected cell in the U2.

If I'm not mistaken, it's just safer to use a protected cell in the U2 even though the U2 does not need it. I don't think you lose out in any way, and you've got additional protection for the battery.

I'm curious though, is it confirmed that a 168a will fit in a U2? I thought only the 168s would fit. If the 168a will fit, I'm going to get one for my U2!!

I think the 2400 mAh 18650 cells are the best for the U2.
They are bare unprotected cells, but the U2 is safe with them.
I have been using them for a while now with no problems.

http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=945

if you are a beginer li-ion user. go with protected cells everytime. besides pila, you have other protected choices at great prices.

U2 is one of few lights out there that supports both protected and bare.

consider dead short dangers (20+ amps for 18650) when handling cells. most importantly over-charge dangers.

don't ever charge your li-ion cell over 4.2V.

li-ion cells have no peak and will keep acepting a charge until thermal overload occurs. that will occur somewhere over 4.3V. then really bad things can occur.

needless to say, one should read up on li-ion use.

again, go with protected if you are new to li-ion.