Oh and you don't need a bigger charger if the new battery has the same number of cells, same voltage, and has a higher capacity. It will only take longer to recharge it. The big NO-NO is to recharge a battery at a faster rate than one time its rated capacity. The charger that comes with the BCPP charges the stock 800 mah battery at 800 milliamps per hour. It will also recharge the 1300 mah battery at 800 milliamps per hour, which is OK. But it will take longer, like almost two hours instead of one. Charging a 500 mah battery with that same charger would be bad.

Always keep an eye on batteries while they are recharging, and place them in a safe place where they pose no fire hazard in case things go bad.