So my Battery is getting old, and I fully charged it (100%) about 4-5 days ago. Put the charger on it this morning and it reads 12.4 volts, and only 59% charged. I didn't have the cables connected, so there was no draw on it- since the 100% charge, again only 4-5 days ago. What do you guys think about losing 41% in only 4-5 days
Battery Discharge Rate
- Thread starter TF360
- Start date
-
The reading on the charger is only a guestimate based on the expected voltage.
If it starts the car don't worry too much.
My neighbor is a worry wort. He has 2 new cars and drives each a couple times during the week.
1 time he had a dead battery so now he puts them on a charger at least once a week.
His charger has a reading on it that says the batteries are 45 to 75% charged every time he puts them on the charger, even if he drove the cars yesterday.
If it starts the car don't worry too much.
My neighbor is a worry wort. He has 2 new cars and drives each a couple times during the week.
1 time he had a dead battery so now he puts them on a charger at least once a week.
His charger has a reading on it that says the batteries are 45 to 75% charged every time he puts them on the charger, even if he drove the cars yesterday.
Last edited:
You need to do a load test. Battery voltage is only a part of a battery test procedure.
Like Mike said, loadtester. They're cheap.
I'm guessing it's toast. If it's lost percentage with zero load, that's kinda telling. A load test will tell for sure.
How old is it? I find that factory batteries last over 10 years and cheap aftermarket batteries half that. If they get run dead now and then its even worse. Many of them quit with little warning. The car just doesn't start one day. My wife's Mazda battery is 10 years old. I'll probably just replace it before winter sets in rather than risk getting stranded at -25C. If it doesn't start she will want a new car 
-
