Canon:
NB-6L
Do not short-circuit the canon battery.Accidental short-circuiting can occur when a metaillic object such as a coin,clip,or pen causes direct connection of the positive(+) and negative(-) terminals of the nb-6l battery.(These look like metal strips on the canon nb-6l).This might happen,for example,wehn you carry a spare digital camera battery in your pocket or purse.Short-circuiting the terminals may damage the battery or the connecing object.
Keep the canon nb-6l battery contacts clean: Clean your battery's metal contacts every couple of months with a cloth moistened with rubbing alcohol. This keeps the transfer of power from your NB6L battery pack more efficient.
If a replacement nb-6l battery is being used for the first time or if the canon nb-6l battery has not been used for a prolonged period.it may be necessary to connect the canon nb-6l battery charger and then disconnect and reconnect it to start the charging.