Hello everyone, here are some key steps you should follow before installing a new 12V battery to ensure optimal performance:
Always check the manufacturing date on the battery and make sure it’s not older than 6 months. Older batteries might not perform as well since they degrade faster when unused.
Charge the battery fully before installation. Most new batteries come partially charged, and fully charging them ensures they work effectively right away. A fully charged 12V battery should read between 12.6V to 12.8V. If it’s below 12.4V, charge it up to avoid any issues with your vehicle’s Battery Management System (BMS), which relies on accurate readings to function properly.
It’s common to pick up a battery and install it directly, but taking these steps can greatly enhance the battery’s life and your vehicle’s performance.
Tan said:
AGM batteries are quite resilient and can handle being fully discharged better than other types, so you might not need to worry as much with those.
True, AGM batteries are more durable against full discharges, but it’s still best to avoid letting any battery fully discharge when you can.
Tan said: @Zeek
Could a smaller LiFePO4 battery work since it doesn’t need to start an internal combustion engine, possibly making it more cost-effective?
That could be a viable option. High-capacity deep-cycle AGM batteries are another alternative, though their terminals might be reversed, which can be a bit of a hassle to fit in a car. Hopefully, we’ll see more tailored options for EVs soon.
Tan said:
AGM batteries are quite resilient and can handle being fully discharged better than other types, so you might not need to worry as much with those.
Just a heads up, I purchased a Bosch AGM battery that only read 9V on a multimeter right out of the store. Always check before you leave the store!
Don’t forget to let your car sit for a few hours after installing a new battery to allow it to recalibrate. This is often overlooked but mentioned in the factory service manual.
Bennie said:
Don’t forget to let your car sit for a few hours after installing a new battery to allow it to recalibrate. This is often overlooked but mentioned in the factory service manual.
Interesting, I didn’t find that in my manual. Could you share the specific section? It sounds like important information to include here.
I had to swap my battery in less than ideal conditions—out in a cold parking lot late at night. Thankfully, the AGM battery was about 80% charged, and it reached over 90% after just 10 minutes of driving.
Phoenix said:
When I upgraded to an AGM battery, I could see the old one was failing well in advance. It’s great to keep an eye on the early signs.
I noticed similar issues. My old battery’s health was dropping quickly—it was at 69% SOH recently, down from 95% six months ago. It was also only holding 12.1V after a long drive.
Zyan said: @Bennie
What’s the best way to check a battery’s power? Do I need a special device?
You can use a simple Bluetooth battery monitor to keep track of your battery’s voltage and health. It’s an easy and effective way to monitor performance without needing complex tools.
Azriel said:
Isn’t the 12V battery recharged by the main drive battery in hybrids like in my BMW? My battery has lasted four years without any issues.
Yes, but all batteries degrade over time, even with regular charging from the drive battery. Sometimes, the charging system itself can fail, which necessitates a battery replacement.