Charging Batteries Connected in Parallel the First Battery Gets Hot and Water Boils
Question:
When I wire two batteries in parallel in my RV the second battery becomes very hot and start to boil. I know that they are hooked up correctly, but not sure why the distant battery is hot and boiling. The near battery is cool to the touch and not boiling when the camper is pluged in and charging the batteries. What do I need to do to fix my problem?? See attached picture.
asked by: Terry C
Expert Reply:
It sounds like the battery charger you are using is overcharging the first battery and the second battery is not receiving any charge. This could be the result of using the old style trickle chargers that are not really designed to charge batteries in parallel.
You may also have one or both batteries that are bad and need to be replaced. I recommend getting the batteries tested and replacing if one or both are bad. Then I recommend using a different charger such as CTEK charger # CTEK56353. This charger will not overcharge a battery and many times it can revive a weak (but not completely dead) battery.
The lead battery is going to get hot and there is bound to be some fluid movement. But if the charge is not getting to the second battery then the trickle charger can overcharge the lead battery. A different charger would fix that issue. I use the recommended charger as do several of my coworkers and it performs beautifully.
Also make sure the battery terminals and cables are clean and free of corrosion.
Products Referenced in This Question
CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power
- Battery Charger
- Battery Charger
- Car/Truck/SUV
- Motorcycle
- Trailer
- Lawn Mower
- Jet Ski
- 150 Ah
- Charges/Maintains
- 12V
- Wall Outlet to Vehicle Battery
- CTEK Power Inc
more information >
Product Page this Question was Asked From
Adapter 4-Pole to 7-Pole and 4-Pole
- Trailer Wiring
- Wiring Adapters
- Multi-Function Adapter
- 4 Flat
- Plug and Lead
- 4 Flat
- 7 Round - Blade
- Hopkins
more information >
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