While charging a small lipo, the charger sounded an alarm. I went to see and found the lipo battery (3S, 300mah) completely burned. Lot of smoke. The fire did not spread because the battery was in a lipo bag. The bag had started to melt but did contain the fire. The overcharging was my fault because I forgot to connect the balance lead. This is the second time a lipo bag saved me from a lipo fire.
Always use a bag when charging. Got mind from HK. I will buy more with my next order.
I will also install a smoke detector right over my charging station.
Be very carefull with lipos.