CoolT

Has anyone had experience with XS batteries? Home - XS Power
Which one did you use for the Rx 8? I'm looking for something that will just drop in and replace the factory battery.

How about other AGM batteries like Kinetic and Optimas? At the risk of getting flamed, have people been having good experiences with recent red or yellow top purchases?

Steve Dallas

I don't have any experience with those batteries, but I can sort of answer you question about my experience with an Optima Red Top. I bought one 2 years ago. It lasted 1 year. It was replaced under warranty and lasted 1 year. They would not replace it again, so I gave up an bought a 24F lead acid from Napa to get my car back on the road (the Optima left me stranded about a mile from a Napa store in August--that wasn't a fun walk).

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Williard

iTrader: (18)

I have a NAPA Premium AGM battery as well. It rocks.

Travis

CoolT

Thanks for the replies!
I know Optimas took a hit in quality after they were acquired by Johnson Controls.
I was hoping they had improved because its a great price for an AGM battery. But if you read the forums, there is story after story about these batteries dying early as opposed to their previous reputation. That's why I'm asking about XS batteries...

Williard - do you happen to know the part number of the NAPA AGM battery? When I search the NAPA site, it doesn't list any NAPA AGM battery compatible with the RX 8.

9krpmrx8

iTrader: (46)

Advance Auto Parts also has a good AGM battery, I just put one in my 335i and if you use the TRT41 discount code online and pick up in the store or get free shipping and you can save $40.00 (off any order over $100). or even use code TRT37 for $30.00 off any order over $75.00 if you happen to get one the cheapest batteries.

Red line envy

I have a red top and havent had a problem. Its been in the car since i bought it about a year ago.

9krpmrx8

iTrader: (46)

Well, you are at a year, that is about how long my first one and my second one lasted before I gave up. They work fine right up until the point they don't. There is no reason to buy an Optima with a one year warranty when you can get a store brand AGM with a 3 year free replacement.

CoolT

I know that the problems with Optima batteries are not consistent but there's enough anecdotal information to make me nervous about getting one. Costco used to have them a while ago but now only stock Interstate batteries. I have brought it in for replacement twice - each about just short of three years and Costco has given me a new one - no questions asked. I would like to get a battery with a higher CCA, but not at a higher cost and more frequent replacement.

I'm guessing its the higher heat in the engine compartment that gives the RX 8 a shorter battery life???

Would the AGM be more resistant to heat?

Isn't there any RX 8 owner with a bank of 300W subwoofers that installed an XS battery?

Thanks

9krpmrx8

iTrader: (46)

Yes heat kills and as teamrx8 and others pointed out, a lot of "race batteries" have a limit of 170F which is way less than an RX-8 engine bay sees in the summer with a hot engine.

I have had my battery (Odyssey PC925) relocated to the trunk for a couple of years now with no problems so far. In South Texas over the past 10+ years in the RX-8 with a normal "premium" parts store battery I have gotten about two years, not much longer. In my other cars I usually get between 3-4 years.

9krpmrx8

iTrader: (46)

For example, the XS Power XS15K has a operating temp limit of 135F. Several times I have used a laser thermometer and a Flir after a hard run on a few things in the engine bay and you won't find hardly anything in the engine bay that is under 200F.


**** my trunk gets hotter than 135F in the summer.

dannobre

iTrader: (3)

I wouldn't put an AGM battery in the engine bay...too hot

I have had Odessey 925 and XS Power 925 series batteries in a couple of builds and find that they don't last long term unless the car is a daily driver or you disconnect it or run a trickle charger. They really don't like to be even partially discharged for very long

I currently run an Optima red top in the race car....only because the store where I buy it will replace it for me no questions asked if it fails.....and a buddy makes really nice aluminum custom battery holders for them

Williard

iTrader: (18)

Dan is correct which is why my AGM is in the trunk .

I'm at work atm but I'll be able to post up which battery I got from NAPA as well. Help build the info. Has anyone created a battery thread already?
Downside to TX heat 9k. Although.... a LOT of good things come from that heat as well.
Travis

wannawankel

You are all correct - the AGM style battery doesn't bode well in extreme heat. Lead-acid works better simply because of the higher thermal load it can manage before failure. This is due to the higher water content of the liquid in the lead acid batteries. AGM works well in powersports applications and rear trunk installs (BMW, Volvo) due to the location and wind cooling (powersports).

9krpmrx8

iTrader: (46)

Yeah I do keep my Odyssey on a trickle charger and actually I charge the battery on my two other cars on a charger pretty often. I found that none of my cars charging system, even my daily, doesn't keep the battery fully charged. It will always take an hour or two on the charger to reach 100%. But I also only work two miles from home so I don't put a ton of mileage on my cars.

Requiem-X8

Mazda battery.

CoolT

Great responses from all!
See, if you don't ask...

I think that if I don't relocate the battery, I'll stick with the Costco lead acid because of their replacement policy. Just saved me the cost of a new AGM battery

Does the Mazda battery have anything special to withstand the heat?

Maybe someone should invent a mod to improve airflow to the battery to keep it cooler??!!

Thanks everyone!

9krpmrx8

iTrader: (46)

Mazda doesn't make batteries.

Steve Dallas

I don't know about S1 cars, but S2 cars have a cooling duct that extends from the battery box to a spot beside the radiator. It helps, but it isn't enough.

acroy

From Battery University
Absorbent Glass Mat (AGM) Battery Information - Battery University
"AGM and other sealed batteries do not like heat and should be installed away from the engine compartment. Manufacturers recommend halting charge if the battery core reaches 49°C (120°F)."

I bet the battery hits 120F pretty quick under the hood of an RX8 stuck in traffic...

I suggest pick an option, based on how much money/effort you want to invest:
1) Low: stick with oe-style replacement in stock location. Replace every 5yrs and don't worry about it. I do this with the dd's and have never been stuck with a failed battery
2) High: relocate to cool location (trunk) and install spendier, lighter AGM or try an alternative such as LiFePO4 battery

9krpmrx8

iTrader: (46)

S1 cars have the cooling duct to the battery box as well.

I have never had a battery last longer than three years in any car I have owned.

CoolT

That's my experience as well probably because of my car choices....I'm gonna go low tech (and low cost) and stay with the conventional batteries that I get at Costco. Maybe when I get the engine rebuilt & ported with a BHR ignition, I'll put the battery in the trunk!!!

Thanks to everyone for the great responses which I think saved me from making an expensive mistake.

Requiem-X8

Are you retarded? there are OEM batteries by Mazda. don't make me slap you.

9krpmrx8

iTrader: (46)

Don't sing it, bring it. Mazda does not manufacture batteries fruity.