I have a 10 year old Sears jump-start kit. I don't know what the battery is in that thing, but it should have been named "Timex". Never quits even with the abuse I give it. I use it as as starter battery, to charge glow drivers, LiPo batteries, NiMh and LiFePO4 receiver batteries, and to power my fuel pump... and I'm sure several other purposes.

It has an internal charger. I just plug the thing into a wall socket at night and the next morning, the green ready LED is lit and off we go for another day of abuse. I don't know what the charger supplies, nor do I care. All I care about is that it works fine, has worked fine in the past, and that I have no reason to doubt that it won't continue to work fine in the future.

Of course, I'm enough of a realist that it won't last forever, but as of now, it ows me absolutely nothing.

If I had to replace it, this is what I would get (the one I have is no longer available):

http://www.sears.com/shc/s/p_10153_1...1987000P?mv=rr

CGr.