Winter Trickle Charging
06-03-2020, 10:20 AM
#1
Rennlist Member
Thread Starter
Winter Trickle Charging
I noticed this anomaly over the winter and into spring which I thought I would share and maybe help someone in the future.
Over the winter I had 2 cars (one 09 997.2 the other 71 Olds 442) on trickle chargers. Both chargers have digital readouts making it easy to monitor the state of the batteries. The 442 was consistently charging and holding a higher charge than the 911. The 911 battery was a new Porsche battery in Feb 19 as part of the CPO inspection. I swapped out the chargers to see if that was the problem – no dice. Even though the lower charge rate (12.2.-12.3) bothered me, I rationalized it off as differences in batteries. Spring comes and both cars are primed and ready to hit the road. The Olds cranked and ran perfectly. The 911 was a little harder to start but cranked and ran well. However, after a week in the garage the 911 failed to crank. I used the fuse box method to get the frunk open and put on 15-amp battery charger. Came back an hour later to find the battery charger had shut down and was not charging, with the readout stating – Failed Battery. The light bulb comes on (finally) low charge rate, isn’t hold a charge check the water level stupid!! Turns out all the cells were low and one was nearly dry. I usually check the water levers in all my batteries once a year but since this was a “new” battery I never checked it -what a mistake. After refilling to the proper level, the charger went back on and what do you know - full charge rate (just like the 442) and with a full charge and no more problems. Moral of the story – If your charge rate is low, check the water levels (assuming it has caps of course).
Over the winter I had 2 cars (one 09 997.2 the other 71 Olds 442) on trickle chargers. Both chargers have digital readouts making it easy to monitor the state of the batteries. The 442 was consistently charging and holding a higher charge than the 911. The 911 battery was a new Porsche battery in Feb 19 as part of the CPO inspection. I swapped out the chargers to see if that was the problem – no dice. Even though the lower charge rate (12.2.-12.3) bothered me, I rationalized it off as differences in batteries. Spring comes and both cars are primed and ready to hit the road. The Olds cranked and ran perfectly. The 911 was a little harder to start but cranked and ran well. However, after a week in the garage the 911 failed to crank. I used the fuse box method to get the frunk open and put on 15-amp battery charger. Came back an hour later to find the battery charger had shut down and was not charging, with the readout stating – Failed Battery. The light bulb comes on (finally) low charge rate, isn’t hold a charge check the water level stupid!! Turns out all the cells were low and one was nearly dry. I usually check the water levers in all my batteries once a year but since this was a “new” battery I never checked it -what a mistake. After refilling to the proper level, the charger went back on and what do you know - full charge rate (just like the 442) and with a full charge and no more problems. Moral of the story – If your charge rate is low, check the water levels (assuming it has caps of course).
06-04-2020, 09:31 AM
#2
RL Community Team
Rennlist Member
Rennlist Member
Good tip. I haven't purchased a regular lead acid battery with caps in 12 years. No reason to use that really old batterybtexh when AGM and now Li-Ion batteries are available for a couple hundred dollars.
06-04-2020, 02:01 PM
#3
Rennlist Member
Thread Starter
I agree, had AGMs in previous Pcars. But since this was a CPO car I got what they put in.
06-06-2020, 10:10 AM
#4
Good idea to check.
I think my next purchase will be battery from Antigravity. Seems to be what everyone is using now.
I think my next purchase will be battery from Antigravity. Seems to be what everyone is using now.
