When I had a Northstar/X2Power group 35 battery, it would routinely charge to 13.0V ( measured 24hr after charging, at around 70F) when it was new. It has the same TPPL construction as Odyssey batteries. As the battery aged in service, the maximum voltage after charging slowly dropped. I took it out of service when it would only get up to 12.5V after charging.New battery arrived and was packaged much better than the last one. This one tested 12.8 volts and 859 CCA.