Battery relocation

Apologies, not sure where to post this so I did so here and in the "shop and garage talk" forum.

Hoping for some help, I thought this would be an easy topic to research but it seems there are just as many opinions as people giving them on-line.

I have a 2003 Toyota Matrix XRS and I want to move the battery from it's present location (under the hood, ahead of the front axle, on the drivers side, up high), to the floor behind the front passenger seat.

What is the proper way to accomplish this?

 - What gage wire is ideal; 0, 00, ?

 - What is the best way to ground it in that location? Am I able to ground the chassis (from the battery) to the OEM seat belt anchor bolt and then ground the engine to the chassis (using a braided ground cable?), or is there a better way.

I want it done right and safe.

Help and thanks

I used 1/0 cable and also grounded the battery to the rear seat belt bolt and added a couple grounds from the engine to the chassis.

My only issue is hum thru my amplifiers / stereo.

I also added a circuit breaker incase of an oopsie.

Oh, I also ran the main power lead in a protective sleeve.

In reply to kevinh333 :

Possibly silly questions. What is the goal of moving the battery? Is this a track car ?

In my old LeMons car, I used 2 AWG welding cable. Negative grounded through the chassis. I think that's probably about the bare minimum as far as wire size, but it worked great for us. Whatever size you decide to use, I highly recommend the welding cable. It's very flexible and the insulation is super tough with great resistance to heat and abrasion.

Thanks,

Stupid question; how does one go about grounding an aluminum block and head 2ZZ-GE Matrix engine?

In reply to kevinh333 :

A bolt and a cable?

In reply to Tom1200 :

Pulled the rear seats and rear cargo pieces out along with other misc. pieces (total weight reduction approximately 200lbs), battery weighs 40-50 lbs and is on the drivers side of the engine bay mounted high and ahead of the front axle, moving it behind the front passenger seat on the floor moves that weight toward the rear of the car and on the passenger side providing a significant and positive changes to weight/balance and center of gravity. 

In reply to obsolete :

WHat about grounding (with an aluminum engine)?

In reply to kevinh333 :

A bolt and a cable?

I am unsure what the issue is.

In reply to Pete. (l33t FS) :

Another stupid question; would there not be an issue mating steel and aluminum?

In reply to kevinh333 :

Do the math on relocating it and the added weight of the new wire vs. just buying a light weight battery.  I know it's a Challenge car but on our Q45 it made more sense to just run a lawn mower battery instead.

If this is a track car, are you allowed to have a battery in the passenger compartment?

If it isn't a track car, is it wise to have a battery in the passenger compartment?

And I agree with Stample, ie, just get a lawn mower battery.

67LS1 said:

If this is a track car, are you allowed to have a battery in the passenger compartment?

Usually it needs to go in some kind of battery box.

Just throw a lightweight battery in the current location and save yourself the hassle. 

kevinh333 said:

In reply to Pete. (l33t FS) :

Another stupid question; would there not be an issue mating steel and aluminum?

All of the other bolts are steel.

Depending on the cars intended use I'd be inclined to simply go with a lightweight battery.

Remote mount battery is kind of a pain in the tail.  Despite using 2/0 cable and being meticulous about connectivity, I measure 30mv of alternator ripple at the battery and 400-700mv of ripple at the battery terminal at the positive terminal underhood that I use to join the new cabling to the car's electrics.

Electronics do not like this.

Thanks to everyone for all the feedback,

The car is not actually intended for the track other than a rare occasional track day, mostly used for B-road blasting on nice sunny warm MN spring/summer/fall days and nothing more, because of this, stripping the interior to reduce weight was not a problem.

You have convinced me to go with a lighter battery in the OEM location.

Oh, any body interested in purchasing a: battery box, battery post connectors, battery junction box, copper lugs? &#*^%^*#@%&

Any good  lightweight battery recommendations based on my described use of the car above?

Pete. (l33t FS) said:

Remote mount battery is kind of a pain in the tail.  Despite using 2/0 cable and being meticulous about connectivity, I measure 30mv of alternator ripple at the battery and 400-700mv of ripple at the battery terminal at the positive terminal underhood that I use to join the new cabling to the car's electrics.

Electronics do not like this.

I've had some strange things happen after remote mounting batteries, but I wonder if done right is it not better for the battery getting it out of the engine compartment?

In two cars we've owned with factory trunk mounted batteries, the batteries lasted a ridiculous amount of time. So long, in fact, I have no idea when they died. We sold one at 11 years old with the original battery, the other is an 09 and still working

In reply to kevinh333 :

Bosch Motorsport lithium-ion battery. For best results don't expose it to Minnesota winters, leave it out of the car all winter long. Should last 10-12 years. 

In reply to kevinh333 :

Bosch Motorsport lithium-ion battery. For best results don't expose it to Minnesota winters, leave it out of the car all winter long. Should last 10-12 years. 

In reply to kevinh333 :

You could just get a cheap lawn battery for $30ish or go really lightweight and pay $100 plus for a lithium battery. If lithium I'd go for a PO4 because of reduced fire risk. Then if you really want to go down a rabbit hole look at the super capacitor battery videos on YouTube.

Is this the one you are referring to:

Bosch Lithium-Ion Powersport Battery; $54.00 at Pep Boys, primary used for motorcycles

codrus (Forum Supporter) said:

67LS1 said:

If this is a track car, are you allowed to have a battery in the passenger compartment?

Usually it needs to go in some kind of battery box.

 

Usually a VENTED battery box. 
 

I researched this a few years ago for a Challenge car, and there technically only 1 box that met both the NHRA and the SCCA rules. It was a vented Moroso box. 
 

And it had to be bolted down a particular way, and required a battery/alternator cutoff switch on the back of the car. 
 

Street car not required, but still a good idea. 

kevinh333 said:

Is this the one you are referring to:

Bosch Lithium-Ion Powersport Battery; $54.00 at Pep Boys, primary used for motorcycles

 

 

Linky no worky