hi Ralph

i would look at the wiki articles below for more info, especially battery life for lithium-ion.

my camcorder uses the batter charger as both a charger and, when the batter is not installed, as a charger (there is an extra adapter that looks like a battery on the end that plugs into the charger, with a plug for the power jack on the camcorder). so the heating problem you see when no battery is installed could be designed into the adapter or could be a failure of the adapter.

if you're more interested in the circuitry of the battery management system, there was a good article re that topic in the Sept. 2009 issue of Circuit Cellar, shown at the link below. You can buy the article ("FROM THE BENCH—Smart Circuitry for Battery Monitoring, by Jeff Bachiochi, p. 66") for $2, or the entire issue for $6. click on "buy PDF" for the article's entry down the Circuit Cellar page below, then click on View Cart. i searched around looking for the development board he used in the article; don't remember the results of my search but i didn't buy one.

james

http://en.wikipedia.org/wiki/Lithium_ion_battery#Disadvantages_of_traditional_Li-ion_technology

http://en.wikipedia.org/wiki/Charge_controller

http://www.circuitcellar.com/archives/titledirectory/221to240.html