[MetalMan]

There is lithium, but it isn't pure lithium. It is in a compound with other elements. If exposed to water, it will not go up in huge flames. In fact, one of the ways to dispose of LiPos is to cut the outer packaging and submerge the cell in salt water.

The Astroflight 109 only sends pulses of 4.35v. It doesn't charge up to that voltage. And because of these pulses, you can charge a battery with the 109 and use a balancer. When it comes to LiPo, it is a good idea to maintain the cells. Things like storing packs at 3.7v per cell and keeping the cells in balance will make your packs last much longer.