Be Cool BC-P2500 Manual página 215

Stop charging immediately if the unit is very overheated. A
battery that becomes very hot or deforms during charging is
defective and must not be used any further.
Do not subject the battery to mechanical stress. Avoid
dropping the battery, subjecting it to impacts, bending it or
cutting it.
When charging the battery, make absolutely sure that the
polarity of the charging plug is correct. If the charging plug is
connected incorrectly, the charger is unsuitable or the polarity
is reversed, there is a risk of short circuit and explosion!
Never discharge the battery completely as this will shorten its
life.
Battery maintenance should be carried out or supervised by
personnel familiar with batteries and the necessary
precautions.
If the unit is to be stored for a longer period of time, it is
recommended that the remaining capacity of the battery is
approx. 30 % of the charge volume.
The product can be charged at a temperature in the range 0-
50 °C.
The product can discharge in a temperature range of -10 °C to
50 °C.
Low temperatures can affect the battery capacity of the
product.