So... if we could touch on battery chargers for a minute I have a couple questions and am in need of some advice. When I first started down the APV road I purchased a cheap Tenergy TN270 charger (from/with my ProVari). Everything was fine but at the time I was using 18650s exclusively. As my collection grew I started getting into other battery sizes and decided to upgrade my charger. Because of all the various sizes I wanted something that would handle pretty much anything I threw at it, including 18350 and 10440 batteries. Safety being of the utmost importance I decided on an Xtar WP6II.
I was pretty happy with my choice, and in light of recent events still am. Last night I put a couple 18650s in the charger and went about my business, checking on them on occasion. I've put the charger on a 3 hour timer so it shuts off automatically. When I went to check after the timer had shut down the charger the two springs where the 18650s had been charging were darkened (in color) and collapsed. I'm very happy that, whatever the problem was, the hot springs worked to protect me. Now my questions:
1. The batteries seem fine now, and when I tested them on my Fluke afterwords they were both right around 3.7v. Obviously the charge cycle wasn't completed and I'm not sure what caused this to happen. Could it have been a surge from the timer I use?
2. Is the charger itself safe to use now?
3. Can the hot springs be replaced in the Xtar WP6II?
4. I just finished ordering a Pila 4-stage charger which will be fine for my 18350/500/650. What about my 10440s?
5. Assuming the Pila can't be used for the 10440s, does anyone have suggestions for a charger that will work with that size?
Sorry for the semi-long post, but thanks for your help everyone.