Second battery
Our camper has only room for one group 24 battery. A few years ago I added wiring and a multipoint switch for an additional battery to go ahead of the rear wheel well but have not used it until now. ...
Forum Discussion
From my experience batteries of different age might mess each other only if left connected in storage for long time.
When you constantly use/recharge the batteries, you always use both regardless minimal differences in voltage.
I run dual batteries in several vehicles and even batteries bought together, having the same manufacture date can show 0.1V difference.
In my boating years I had my travel trailer in storage close to the lake.
With no hookups, I was taking trailer battery home for recharging, but for emergency brakes and short run of water pump I put old motorcycle battery in it.
The recharged big battery would connect with alligator clips to much smaller and much older battery and work whole weekend just fine.
When you constantly use/recharge the batteries, you always use both regardless minimal differences in voltage.
I run dual batteries in several vehicles and even batteries bought together, having the same manufacture date can show 0.1V difference.
In my boating years I had my travel trailer in storage close to the lake.
With no hookups, I was taking trailer battery home for recharging, but for emergency brakes and short run of water pump I put old motorcycle battery in it.
The recharged big battery would connect with alligator clips to much smaller and much older battery and work whole weekend just fine.
