Dual Battery + Charger ?

[ABarbarian]

Just bought a new to us 2018 Bennington 22……. My history is fishing boats so I was thinking I needed an onboard charger with the radio always playing. But after researching a little I’m not sure that’s necessary. Battery #2 seems to only be for the motor. Either battery can and does start the engine when turned to 2/both so I guess it sits as a backup. Curious to how the Bennignton veterans use the dual battery setup and if an onboard charger is necessary?

 

[Pbakk]

I look at the on-board charger (or solar charger) as insurance. With two batteries, you should be ok unless your trips are short and radio playing / electronics are long. It also depends on how many years you try to stretch out of your batteries. In my case, I have Sea Legs (Ultra Legs), thus I have more reason for the insurance of a charger.

 

[LaurencetheAdventurer]

Wiring seems to vary between years and dealers, generally, either battery should support the boat. Note that unless you have an aftermarket switch installed, it only charges the battery to which it is switched. We float more than go - which meant that after 4 seasons I had two batteries that would no longer hold enough charge, even after being prudent during long runs to charge both. I have no ability to charge over the summer when the Benny is in the water. So, I am converting to Lithium this year - where the deep discharge does not destroy the battery.

 

[Potomacbassin’]

Obviously depends as others have stated what your draw is from accessories - in my case, the radio and lighting is seldom used with the engine off so recharging "on the go" is sufficient. In over 5 years I'm still on the original 2 house and crank, and only charge from my outboard.

If you sandbar it for extended periods of time with powered subs booming, and only run 10mins back to the dock/ramp then you'll likely need to shore charge. It all depends!

 

[BigKahuna]

Welcome to the forum Barbarian!!! If I start the boat on Battery 1 and cruise around, or ski/wakeboard, and then hang out in a No wake cove for a few hrs. to eat and swim....... When we leave that cove to cruise around/ski wakeboard/go home I'll switch to Battery 2 for the remainder of the day!