I think it is important that we get battery voltage testing done right. This is a problem area for amateurs as well as new mechanics. Voltage on an unladen battery means nothing. I will repeat that voltage means nothing when it is not being used. While a battery's unladen voltage should be 12.6 (never mind the shorai), that voltage merely explains the pressure exerted on the few, or many non moving electrons. And that is the problem, you have no idea of the amount of electrons available- the batteries ability to carry out the chemical reaction to release the quantity of electrons necessary to do real work, and it does not give you any idea to the internal resistance that the battery has to the movement of the electrons. I have seen batteries test unladen perfectly fine, but under a load turn out to be down about 2.1 volts from where they should be. This is due to a broken positive or negative strap within the battery leaving out one cell from the party. I have also seen batteries that test 12.6 with no load and 8 volts with. This is largely due to plates with sulfate buildup, or rather when charged they have not converted the lead sulfate back to sulfuric acid and lead. so, for future battery testing, you can look at the unladen voltage but realize that this doesn't mean much, test the voltage with a load and it should not drop below 10 volts, at about 9 the computers stop functioning altogether. Happy Battery testing.
;D 
