Battery puzzle, is there a problem here?
Posted: Sat Mar 18, 2023 4:32 pm
Got my 3.2 engined 911T going today.
Routine is to charge the 2 batteries, change oil etc and start up. Done this for 30+ years, all ok, but today...
The car has sat still in the garage since last September, batteries connected, car electrically OFF.
The two batteries are Bosche Silver Plus S5 12V 250A 25Ah and are certainly 10 years old. Always been perfect from new.
Put one on the charger, and the charger showed Zero Amps. Voltage was 10.4 V.
Put the second one on the same charger, charger showed 6 amps and I left it charging for 30 mins. = 12.6Volts off the charger.
Put first battery back on, no movement on the ammeter but left it for 30 mins. Voltage now 12.3Volts off the charger. Charger still showed zero charging current.
Put both batteries in the car, started the engine and all normal, usual 3.2 churn and fired onto 6 as it always has.
Left it ticking over to warm up so i can check the oil level etc. This took about 20 mins.
Shut the engine off and checked the volts on both batteries, both 12.6 volts.
I'm puzzled why the charger did not show a charging current on one battery, but a normal 6 amps on the other. Time for new batteries?
Routine is to charge the 2 batteries, change oil etc and start up. Done this for 30+ years, all ok, but today...
The car has sat still in the garage since last September, batteries connected, car electrically OFF.
The two batteries are Bosche Silver Plus S5 12V 250A 25Ah and are certainly 10 years old. Always been perfect from new.
Put one on the charger, and the charger showed Zero Amps. Voltage was 10.4 V.
Put the second one on the same charger, charger showed 6 amps and I left it charging for 30 mins. = 12.6Volts off the charger.
Put first battery back on, no movement on the ammeter but left it for 30 mins. Voltage now 12.3Volts off the charger. Charger still showed zero charging current.
Put both batteries in the car, started the engine and all normal, usual 3.2 churn and fired onto 6 as it always has.
Left it ticking over to warm up so i can check the oil level etc. This took about 20 mins.
Shut the engine off and checked the volts on both batteries, both 12.6 volts.
I'm puzzled why the charger did not show a charging current on one battery, but a normal 6 amps on the other. Time for new batteries?