Charging batteries from batteries

[dandman]

I have discharged 2 batteries 3 times for 1amp hour at a time and recharged those batteries from another single battery back to their original charge state for the loss of .01 of a volt per charge hour. IS THIS UNUSUAL

[dandman]

Maybe Im short on detail so here goes. The discharging batteries started at 12.64v and were discharged for 30 mins at 2.1 amps. Then connected to the feeding battery, which started at 12.83v. The discharged batteries took 2 hours to be returned to 12.64v and feeding battery on completion had dropped in charge to 12.81v. This was done 3 times without interval between discharge and recharge and the subsequent drops in voltage of the feeding battery were .01v per hour. In my untrained ignorance, I am pretty sure that is more than 1 from 1 but would appreciate an educated persons plain language explanation if it is not. Happy to discuss further and thanks in advance.

[onthecuttingedge2010]

You ever heard the term, A bad battery will make a good battery go bad?

[dandman]

Thanks for the sarcasm. I charged these batteries fully and discharged them at 68.8 amp running a 700watt 240v drill through the 1kw inverter before starting this alternative way of recharging them. Does anyone have any educated input please .

[nightlife]

 I don't think are including the amps in your measurements. You may show a certain voltage but you need to know the amps as well. The best way is to load test the battery used to charge both before and after and then load test the ones charged before and after you think they are fully charged. Once you do that, you will then find out exactly what was lost.