Metallica,
This is great info for most newbies, don't feel bad sometimes you have to learn the hard way.

IMHO fast charging is just a bad thing, I use the Accu-cycle and charge my 2000's at .125 for the cycle time of 15 hours., this is only after I discharge. Also it was mentioned that most of the time you will never use more than 1/3 of your large pack, keep this in mind when charging, in that case I put it on .050 setting and let it go overnight, similar to a wall wart. 12 hours on a WW is the same as 600 Mah or 12 times the output rating on your charger.

Think about your 1 amp rate for 2 hours, 2000 Mah for a pack that only needed 500.[X(][X(] hence the explosion.