Unsealed lead batteries that go through proper solution maintenance can definitely last decades - I have a forklift that keeps almost 1/2 its original charge an

Unsealed lead batteries that go through proper solution maintenance can definitely last decades - I have a forklift that keeps almost 1/2 its original charge and it was made in 1982. but I have flushed and cleaned the cells a few times and keep track of the pH when I top them off.