Newbie, adding another house battery

[Timintn]

I have a 94 gulfstream conquest that I've been restoring. I want to add a second house battery but the current battery is in the engine compartment. I'm thinking of adding the battery in the basement just behind the cab or do the batteries need to be together? Or... Do I move the engine bay house battery to the same spot and add extensions from the engine compartment cables to the new location? If I go with flooded cells, I'll add a vent in the bay door. Thanks!

 

[Kevin D Pem]

AGM batteries don't have an off gas problem. That opens up where you might put them.

The battery institute tell you that you should not use two batteries in the same bank that are over six months apart on manufacturing date. The new battery will be the one to suffer.

With this information and some 10AWG wire you should have some answers.

 

[Timintn]

Thanks. I plan on buying the two batteries together. Any issue of they are approximately 6' apart?

 

[Kevin D Pem]

Thanks. I plan on buying the two batteries together. Any issue of they are approximately 6' apart?

Are we talking series or parallel?

 

[Timintn]

Two 12bcc in parallel

 

[Timintn]

Ehh, vdc

 

[Kevin D Pem]

if the reason for more batteries is an inverter the inverter cables should be the same length. Because the cables between the batteries change the resistance make sure you put the ground on one battery and the positive on the other this will make a closer to equal draw, or charge on the bank.
really that should be done on any battery installation but the more the batteries are placed apart the bigger the problem becomes.

 

[Timintn]

I don't have an inverter, just trying for more amp hours for boondocking

 

[Kevin D Pem]

I like terminal posts when this is nessisary. Most all things should come to the post making battery service easier Each battery should be hooked together with cable based on future plans, but all loads should be hooked up to both batteries. this is done with one battery grounded and the other with positive loads. the terminal posts just keep the spaghetti from being an issue while adding water. I don't use flooded batteries anymore. I am using batterymax 200ah batteries an AGM. They say AGM will last twice as long as flooded. The ones I have are made for solar setup and have an advertized life of 7years.