Intelligent chargers will rapidly charge a battery to full capacity (in 2 hours or less) then go into trickle mode keeping the battery topped up without over-charging and damaging the battery. (Mobile phones have intelligent chargers).
If radios are left on charge for long periods, a weekend for example, the battery will not be damaged. With most chargers the batteries can be left in the charger indefinitely. Ideal for emergency and standby use.
Every radio Wildtalk sells has an intelligent charging system supplied as standard.