Gimpy wrote:
Am disabled & am using an electric scooter to get around outside. Put
in 2 new batteries ( lead acid type ) (U1 Ah SLA ) the start of last
summer & by late summer one went bad & was replaced under warrantee .
Now the remaining one of the original pair is starting to go & was
wondering if it would be ok to run with the some what new one from
last fall & put in a new one before much longer to replace the one
going bad. OR be best to keep the somewhat used one & put in 2 brand
new ones now ?? On S.S. so funds are limited.......Thanks Gimpy..

IMO:
I'm disabled but do not use battery powered equip. Yet. So I have zero
specific experience with your appliaction. That said:

It sort of depends on where you are and intend to go. If it could strand
you somehow where it'd be difficult to get assistance, I'd go for the new
ones. If you're always around assistance, maybe try to use up the older
ones.

Those seem like awfully short lifetimes for lead-acid batteries. Do the
specs indicate a normal life for these batteries under your use conditions?
Perhaps some research into alternative battery types and manufactuers is
in order? I'd expect lead-acids to have a life of two to five years if
properly used and maintained/charged.
Perhaps more frequent charging would help, if it's possible, and never
let them get to near dead before charging.

Pop`