Stop in for a cup of coffee
Average battery size, 24 hours on 2 amps.
I worked at Sears back when I was in college... They had a charging station with copper rails and wires with aligator clips that we would put the batteries on to charge them... we would give the customer a free loaner to get by and tell them to come back in three days...
The loaner batteries were ones that were traded in under warranty that we were able to recharge and make good again...
After recharging the customer's battery, we would load test it before giving it back to them to make sure it was good... If it tested bad, they would pro rate a warranty exchange for them if it was out of the full free replacement time frame...
I worked at two different Sears garages, each manager had his own philosophy on exchanging batteries... One guy would exchange them and pro rate a new one even if the old one wasn't bad to make a sale on a new one...
The other manager would not exchange or warranty one unless we tested it and it failed... He refused to exchange a battery under warranty if it wasn't bad....