Hey quick question guys/gals

I have an optima yellow top i just recently bought.... 34/78

I know others have mentioned hooking there bat straight to the cars battery (parallel if you will) without any problems, YET on the optima website it states:

9. Can I hook an OPTIMA up in parallel with my other battery?

No, when hooking batteries together in parallel they should be of identical make, model, and of similar age.

So can anyone confirm that there is no harm in hooking my optima in parallel with my car stock battery?

tried to search this but found no info

Edited March 14, 200718 yr by theabunai

There shouldn't be any problems.

Optima can't know every make and model of battery that users might connect to their own product, so that statement is just covering their ass from a liability perspective.

YOu do run the risk of draining one battery from running another in parallel and possibly wiping both out. You also run the risk of shortening the battery life of one or both as well.

Jimj that makes perfect sense.... liability I should've seen it that way lol

Tirefryr - actually i don't plan on running the system with the car off, always with the car on.... I don't want an isolator as it causes resistance (so i hear)...And once i get another 50 bucks froma few side jobs i'm gonna get a Red top for the starter bat.

The battery guy told me that optimas ESR value is low so it won't discharge the other battery quickly enough to cause concern and as long as i run my car within 48 hours it should be no issue (i work 5 days a week, go to school m, w and sat since i'm an 4th year apprentice in sheet metal/Air conditioning) so my car gets mileage...

But then i read that statement on Optima and thought chit whats that all about...

Oh and BTW thank you very much for the help and advise

Edited March 15, 200718 yr by theabunai

One battery can drain another even while the car is running. Just be aware that there are risks and there is no way to say you will be 100% safe.