Hi,
I am charging a 12 V lead acid battery (Enersys 12 V 7 A h) with a current limited voltage regulator circuit (based on an LM317). I am monitoring the battery current and voltage with a microprocessor. I want to know what would be the best indicator as to when the battery is fully charged.
I am counting amp hours into/out of the battery (using the microprocessor) to get an estimate of the SOC (In the battery application manual the efficiency varies as a function of SOC). I didn't think this would be very accurate at determining when the battery is truly 100% charged.
The current drops as the battery charges, but I'm not sure what threshold to use in deciding when to stop charging (in the data sheet it says the current drops to as low as .002 C, or 14 mA during the final stage of charging). The other idea I am considering is looking for the charging voltage to reach 14.4 V (the open circuit voltage for the output of the charging circuit).
Any advice would be greatly appreciated.
I am charging a 12 V lead acid battery (Enersys 12 V 7 A h) with a current limited voltage regulator circuit (based on an LM317). I am monitoring the battery current and voltage with a microprocessor. I want to know what would be the best indicator as to when the battery is fully charged.
I am counting amp hours into/out of the battery (using the microprocessor) to get an estimate of the SOC (In the battery application manual the efficiency varies as a function of SOC). I didn't think this would be very accurate at determining when the battery is truly 100% charged.
The current drops as the battery charges, but I'm not sure what threshold to use in deciding when to stop charging (in the data sheet it says the current drops to as low as .002 C, or 14 mA during the final stage of charging). The other idea I am considering is looking for the charging voltage to reach 14.4 V (the open circuit voltage for the output of the charging circuit).
Any advice would be greatly appreciated.