When working with the battery, be careful, as it contains a solution of sulfuric acid, do not allow the electrolyte to come into contact with the skin and eyes. If this does happen, rinse the affected area thoroughly with plenty of water. To avoid gas explosions, do not use open flames, sparks or heaters in the immediate vicinity of the battery.
Because the vehicle has a special type of battery (with piping for venting corrosive and explosive gases to the outside), replace it with a battery of a design that can be connected to the specified handset.