Charging RV Batteries

[NINJABABY]

I know there is a thread about it but I have a different question/concern.

I am new to RVs and bought a USED RV recently. The seller told me to replace the battery. So I bought a new one and the old one is sitting on the ground doing nothing. Dah!! I understand that I need to use either a power source or a generator to charge the batteries.

My questions is what will happen if I connect both batteries together in the following way?

old battery positive with new batter positive AND
old battery negative to new battery negative
(just like we jump our cars in winter)

1. Will it be safe?
2. Will there be too many "amps going to RV"? (I don't know if this is even a correct question )
3. Will the charger charge both the batteries or wont' charge any of them?

Please ignore my ignorance about these questions.

Thanks a lot

[traderal]

Not a dumb question.

Some info: https://rvnerds.com/2017/08/07/elect...gescapacities/

[BUSHRVN]

It’s never good to connect an old battery to a new one, ever. The old one will degrade the new one. Paired batteries should always be of equal condition and age.
Charge them separately.

[alpineguy]

Originally Posted by BUSHRVN

It’s never good to connect an old battery to a new one, ever. The old one will degrade the new one. Paired batteries should always be of equal condition and age.
Charge them separately.

X2

[bat119]

Originally Posted by BUSHRVN

It’s never good to connect an old battery to a new one, ever. The old one will degrade the new one. Paired batteries should always be of equal condition and age.
Charge them separately.

X3!

[MyAlberta]

While I agree that batteries of different capacity should not be grouped, batteries of similar capacity (actual) will share the load as well as the charge, and need not be separated. The real question is why one would introduce an unknown into RVing. Best to have everything thing in top condition before hitting the road.