I have two crazy carts bought last Christmas and used once put in the garage and now will not charge on one I get a red light for about 1 minute and then it goes green the other does not change colour if this is the battery is there anyway of replenishing the batterys as iv looked and the conectons look sealed on
about 5 years ago
If the batteries were in storage for a year without being recharged then, unfortunately, they are permanently damaged and will need to be replaced.
SLA batteries slowly self-discharge over time and need to be recharged at least every month in order to keep them working.
If an SLA battery pack is not recharged after each use and on a monthly basis when in storage then its Voltage level starts to decrease. This decreased Voltage level causes sulfate crystals to form on the battery's internal plates which obstructs the battery's ability to be recharged and produce sufficient quantities of electricity.
When this happens the battery pack may look brand new on the outside however its internal chemistry has been damaged and the battery pack will need to be replaced.