I dont know how accurate the readings are but they are fairly repeatable. Testing various good and not so good batteries I have showed more or less resistance as expected. One reviewer says it puts no load on the battery because it displays the same voltage as a regular multimeter, this is not true. The displayed voltage is the unloaded voltage but it does put a load on to test the resistance. I put a current meter in series and it uses a few short pulses of load to do its calculations.
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