Split Charger for sub battery

[mikee55]

Hello everyone,
Been having some grief with my
car of late. The battery was undersized and didn't have enough oomph, seeing as its a Diesel. So I've been using a spare battery in the back, wired in parallel. Ha,ha, naughty, the batteries weren't a match and consiquently, this morning, my main battery died. Actualy, this fternoon I had a go at starting it and got the smell of rotten eggs from the enine bay and the engine would not turn at all, soley from the main battery. I was told about none matching batteries and I had no choice, I've been using the car alot lately, because I'm moving house.
This evening, I had to fork out some readies for a new battery.

Anyways, sorry for babbling, I just wanted it known that the above battery pack lasted nearly 4 weeks. So if this post comes up in a search, you might get a month!

On the plus, my sub amp was also taking its feed off of the second battery, and boy what a tweak! I couldn't believe my ears, the extra juice was obviously helping no end but I think that possibly the battery also acted like a big smoothing cap and lowered alternator noise, (is that right, please?). Either way, Having it was a big plus to the system. What I'd like to know, is this; Could the battery stay, and feed the sub amp, but, not be connected o the main battery? That way, I don't need to buy an identical battery. Also I would use a split charge circuit, and just use it like a Leisure Battery. Does anybody know of a good way of doing this?

Cheers

Mike

[zigzagflux]

Look up battery isolators in Google or something. Common in marine and RV applications.

http://www.hellroaring.com/

[ppia600]

They're pretty cheap at autozone (isolators) Get the heavy duty one.

[mikee55]

Many Thankyous for replies
Mike