The tall, blue Northstar/Energy1 battery (on right) might require some modification to battery boxes or compartments to fit.

AGM Batteries Test Update

East Penn (again) and Northstar submit to the PS torture test.

In our recent test of absorbed glass mat (AGM) batteries, we cycled five different batteries through 30 deep cycles to 11.7 volts but only partially recharged them for one hour after each discharge cycle at a charge rate of 46 percent of battery amp-hour capacity. (See PS May 2015 online.) The object of the exercise was to demonstrate just how quickly sulfation, which is caused by keeping a battery in a partial state charge (PSOC), can reduce the capacity and eventually permanently ruin a good battery.

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