Hello together, I know there are various topics. Maybe someone still wants to discuss it again or again or to give help. After she let me down yesterday morning at 1°C, my motorcycle battery wanted to bring something to the front. I read it into the matter today the whole day. In my case this is a 12V/12Ah motorcycle lead battery about 2-3 years old and becomes 3/4 of the year 2x daily for 10km but should be generally reverberated. Well, how is it best to do this? First of all, I got an acid lifter and battery acid for a precaution, of which. I still have water. The battery now hangs with 300mA on the low-cost charger. Before charging directly after driving I measured the voltage, this was at 13,8V which really surprised me. Level corrected and off to the charger. Let’s see what I measured when it is “fully” charged. My questions or instructions skusion basis is based on the following statement from Wikipedia: “The acid density at the same time represents a measure of the state of charge. It is about 1.28 g/cm3 with full accumulator (100% charge) and 1,10 g/cm3 with unloaded accumulator (discharge > 100 %, deep discharge!) ” With corresponding graphic:charging state of a battery over idle voltage 1. If according to graphic 100% charge state are reached at 12.7V how can I measure my battery 13.6V voltage? 00% charge state? 2. If battery acid is max 1.28g/cm3 how can it reach over 100%? Shouldn’t the acid concentration have to rise to over 1.28 theoretically? 3. Can I assume that an internal cuz circuit of a cell has not occurred during the voltage measurement (approx.2V per cell)? Since the voltage alone is not a statement for an intact battery, but rather the capacity is characterized by a persistent starter battery I must probably look in the “full” charged state whether and how quickly the voltage decreases or collapses under a defined load. To do this, I would take one or two H4 light bulbs and measure how long it takes until the voltage has dropped to 10,5V. Further considerations after I have done this and not to make the contribution any longer.