Recently A family member gave me 4 Yuasa 12 volt 7ah batteries as they would be useful to make an extra battery pack for a hub motor. He told me that they are new and unused, they still have the plastic caps over the connectors and were still in what looks like the box they were delivered in. However I do not know how long they were sitting around for.
I put them on a float charger and they all reached the float voltage within a few minutes, then I disconnected them. After leaving them for a day I measured the voltages and was surprised by the results, which were: 12.69v 13.09v, 13.09v and 13.14v. Leading to my question which google has not been able to answer thanks to overwhelming links about recharging them. To my knowledge they should produce about 12.7v, what is causing three of them to produce a much higher voltage?
I put them on a float charger and they all reached the float voltage within a few minutes, then I disconnected them. After leaving them for a day I measured the voltages and was surprised by the results, which were: 12.69v 13.09v, 13.09v and 13.14v. Leading to my question which google has not been able to answer thanks to overwhelming links about recharging them. To my knowledge they should produce about 12.7v, what is causing three of them to produce a much higher voltage?