Recommended 12v Battery to 12v Battery Charger
Updated 11/03/2025 | Published 01/07/2025
Question:
Hi , optimate 12vdc to 12vdc charger okay to stay in place between coach 12v batteries and the 12v chassis batteries while coach is plugged into shore power and solar power is connected to the 12v house batteries? I’m hoping to keep chassis batteries charged this way ?and also can it stay in place while engine is running and alternator is charging chassis’s batteries? Thanks for any input here!
asked by: Jeff F
Expert Reply:
Yes, that is ok Jeff! The OptiMate Smart Battery Charger item # MA99JR will work great connected to your coach and chassis batteries while you're plugged into shore power. It's going to recognize your batteries level and adjust the charge based off of that level.
The OptiMate item # MA99JR can stay connected while the engine is running. I have linked a review video below so you can see the features of this charger demonstrated.
Product Page this Question was Asked From
OptiMate Smart Battery Charger - DC to DC - 12V - 2 Amp
- Battery Charger
- Battery Charger
- Car/Truck/SUV
- 12V
- Charges and Maintains
- AGM
- Gel
- Lead Acid
- Lithium
- Vehicle Battery to Auxiliary Battery
- Smart Charge
- Trickle Charge
- OptiMate
more information >
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Jerred H.
11/3/2025
Hey Jeff, how did things go using the OptiMate charger between your coach and chassis batteries while on shore power? It’d be great to hear if it kept both battery banks charged the way you wanted. Your update could make it easier for others setting up a similar system.