BillC3

Discovered at the club race last weekend that my SPB is quite a bit overweight (163 pounds with <1/4 tank of fuel). It looks like an easy way to drop 25-30 pounds will be to replace my stock battery with a lightweight battery (rules say min allowable battery weight is 10 pounds).

What battery(ies) would y'all recommend? What have you tried and did you have good (or bad) experiences with them?

The lithium batteries look interesting, but are expensive and have limitations (they don't like really cold or hot weather, plus potentially flammable). There are AGM batteries in that weight range (like Odyssey PC545), but they're intended for smaller vehicles/toys. Would they hold up in a race car? I've read a number of poor reviews of Braille batteries, so not sure about them.

PGas32

I just installed the Odyssey 680 at VIR, which saved about 12lbs over the 925 that I had been running. Both work fine, but I do turn the kill switch off at night and when I'm not using the car.

Matt Romanowski

What's the group opinion on Antigravity Lithium? I just put one in my 914. It was ~$300 and weights 4 lbs vs an Optima at 24lbs. They make larger car batteries with higher mAh ratings. I went for the largest powersports battery as my car really only has the ignition to run. I've used one of their jump packs for a long time and been really happy, so I thought I'd try the battery.

ace37

The rules specify a minimum battery weight of 10 lbs. The larger H6-H7 group may work and would supply a lot more power than an AGM battery. They run around $800.

I picked up an 11.5 lb Braille B14115 AGM battery which I understand is very similar to the Deka ETX14. I bought it because I could get it fairly quickly and at the time that mattered. I read that a lot of the Texas and Colorado guys use the Deka ETX12/14 batteries. The Braille is rated for 360 CCAs which seemed like plenty. I have an oil, trans, and ps cooler plus an accusump. It’s not enough power. It starts just fine the first time but over the course of the day it loses voltage. By the end of a single DE day (~5-10 starts) it can’t crank the car. I’ll be looking for something with more capacity soon. If I didn’t have as many cooling accessories it may have been adequate.

I believe I need to pay more attention to the Amp-hours and not just look at CCAs. The B14115 is only 15Ah. That’s not much.

Found this on the Deka/Braille batteries:
https://www.iwsti.com/forums/2-5-lit...a-battery.html

The Odyssey 680 is a popular choice. 16Ah so it’s similar to those small Deka/Braille options.

I also don’t have any driver cooling and may need to change that. The coolsuit alternative by chillout systems sounds sounds interesting but reportedly takes a lot of current to run with a peak draw of a whopping 28A. More on that here:
https://rennlist.com/forums/racing-a...otorsport.html
https://barrysracing.home.blog/author/barrywhoami/

Reducing down from a 5 7/8” pulley to a 4” pulley cuts rotation speed to 68% of the stock speed. The stock alternator appears to be a 150A unit so we effectively have about a 100A alternator.

Antigravity

Hey BillC,

Scott from Antigravity Batteries, I would like to clarify a few things for you....

1- First I want to address the safety issues because that is the most important. You expressed that Lithium is potentially flammable, and that is CORRECT, but with a few important caveats.... The first being is that the batteries that have a potential to go into Thermal Runaway (Battery melting down) do not have the BUILT-IN protections in the form of an on-board Battery Management System (BMS), and often use a lower quality Lithium Cell. Antigravity as well as a few other companies are using a FULL BMS that protects from the issues that cause Thermal Runaway. For a Lithium Battery to get into a Thermal Runaway condition requires a specific set of circumstances that can occur with an UN-PROTECTED Lithium Battery. Usually this is a severe over-discharge, then a fast re-charge of the battery which creates interior heat in the cells, or by over-charging the battery significantly by using a wrong charger such as a 16v charger on a 12v Battery. But a battery with the built-in BMS does not ever get to these conditions because the BMS won't allow the battery to over-discharge or get over-charged. So with a high quality battery that potential is eliminated.

While there are still some companies such as Braille, offering Lithium Batteries without protections, and they can be used perfectly without issues IF they are kept care of, but the fact is they are NOT a completely safe method compared to the modern BMS Technology. Braille is mostly a full Race Battery, and they have chosen to not make Batteries with built-in protection which I completely dis-agree with, but that is on them.

2- The Cold and Hot weather thing is sort of accurate but again with caveats. Keep in mind when Lithium Batteries for Vehicles were being used in the past people were using the smallest battery possible since Lithium is so powerful. For example you can use a 5 amp Hour Battery that weighs 2.2 lbs to start a V8 motor easily... but that little battery does not have any Capacity to run lights or crank that same engine when it in close to freezing weather... whereas if you used the proper size lithium battery for your vehicle it pull off a cold weather start easily. But I will also state that if you are driving a Work Truck in Montana during the Winter I would look to Lead/Acid. Lithium does have resistance on the FIRST start attempts because the cold makes internal resistance in the battery, but after the first start attempt the Lithium is self-warmed by a current discharge and will come back to full power in a minute or so because it will self warm on the current discharge. When talking Racing and Sports Cars they are usually not driven in freezing icy temps, but if you have a proper sized Lithium Battery it will not flinch in the cold. As an example I have a 2005 Toyota Tacoma, I take that on Snowboard trips and leave it sit for 4 days in Mammoth and the temps are from 4 to 24 degrees F and it started each time with ease using our 40Ah model... As far as Heat and Lithium... not worried. We are used in Trophy trucks, IMSA Cars, SX/MX, Drifting Cars and much more and even when directly in the engine bay on a Turbo Race Cars in Global Time Attack and the heat is not harming the batteries... but your Boxster Battery is not even in the engine bay.. so that is nothing.

3- Now as far as expense.... for sure Lithium is more expensive, it cannot be produced cheaper than lead/acid, also in our batteries it has a built in BMS so it does cost more to produce. But in terms of facts vs value I can explain it like this... You get about 2x the cranking power of a similar size Lead/Acid battery, Lithium rated at over TWICE the Cycles of Lead/Acid Batteries which means theoretically TWICE the lifespan on average. Now add in the fact that the battery CANNOT be damaged by OVER-DISCHARGE (like a Lead/Acid battery would be) because it has a BMS to prevent that, which then means you won't accidentally hurt the battery if you left the lights on, or the key in the ignition. Now add to that the fact it is up to 70% lighter than lead/acid, and is not effected by vibration as Lead/Acid is and if your interested in those factors it absolutely makes a good value proposition. So that initial higher cost seems to make more sense though the cost of entry is higher.

A word on Cost...someone mentioned our Battery was $800 dollars... but please note, that is for the 40Amp Hour model, our highest priced model. We have multiple options for MUCH less cost.... but the fact that you have to have a minimum of 10lbs which would put in you the territory of our 24Ah Models. They weigh about 12lbs... and are in the range of $650. But keep in mind this 24Ah battery also has built-in WIRELESS JUMP-STARTING....so you will NEVER come back to a Dead Battery that won't start. It also has a full BMS with all the protections, and is the exact OEM fit for Porsches.... so there is no funky mounting it just drops in using stock mounting and you go.

Now as a FYI about Braille Lead/Acid Batteries... as ACE mentioned, they are a re-labled DEKA battery. DEKAs are about half the Cost and make all Brailles Lead/Acid Batteries. And the Carbon Fiber AGM by Braille is just a Carbon Fiber shell that is a put on the OUTSIDE of the typical Plastic Case of the Battery of the DEKA Battery. It does not make it lighter or offer anything more, you are paying for a Carbon fiber shell that wraps the existing plastic case. DEKA is in most cases a quite good battery, but you have to watch for over-discharge on a lead/acid battery that hurt them and the smaller lead/acid batteries can discharge easy and really do not supply the quote Amp Hour rating they state.. because they are tested on a very low amp draw which Lead/acid can handle well.

If you have any questions let me know. That 10 pound rule is sort of a bummer because we have some smaller options that would be perfect for Boxsters and perform awesome that weigh around 5-7lbs, and are very affordable.

This is a video of what our new batteries do....

Antigravity

Well here my opinion....for what its worth being my company....

First thanks for going with us. If you have any issues, you let us know and we will take care of it, we completely stand behind everything we offer. But my opinion is you will use it for many many years without issues. If you have the newer RE-START versions with the built-in protections that is what will allow the battery to not be damaged by most things. The most common cause of damage to any type of battery is just an accidental over-discharge. Once a battery is taken below it lower voltage threshold (in general 10.5v) the risk for damage to occur is there, which will dramatically shorten lifespan, cranking power, and capacity. If you take it down inthe 6v range for a while then that is definite damage area for any battery. But you won't have to worry about that with a RE-START Battery since the battery would put itself into a SLEEP MODE if it goes below a set point we make to keep it healthy.

I am quite fond of the 914.... I had a 1975 and in 1995 when I was younger and stupid, I put a V6 Buick Motor into it, which as an adult now I should NOT have done, but it was quite the builder experience and I learned a tremendous amount. I ended up selling it a few year later but it was one of those Cars for me that started me on my Motorsports journey.

Bull_D

[QUOTE=Antigravity;15939824]


That 10 pound rule is sort of a bummer because we have some smaller options that would be perfect for Boxsters and perform awesome that weigh around 5-7lbs, and are very affordable.

/QUOTE]


I couldn't agree more. This rule has never made sense to me. Lots of guys struggle to get down to min weight due to cage weight, their physical size, among other things. With the new battery tech, this is a great place to drop weight with a simple part swap. a min weight is a min weight, so it is no advantage to run a 5# battery over a car with a 24# battery if they are both down at min weight. allowing "free" battery choice has the chance of saving a few bucks, as mentioned by being able to purchase the less expensive, smaller version.

BFT3.2

I've been running a Odyssey 680 (15lbs) in my car for three years and have had zero problems. I also hit the kill switch overnight.

C4 Pazzo

Odyssey PC680 works well for me. Lasts 3-4 years. But you need to use the kill switch overnight and make sure it doesn't allow any power draw. I have an electronic kill switch and had to wire in a second circuit breaker to isolate the battery from the kill switch - works great.

PLNewman

Has anyone ever seen the 10 pound rule enforced? In the past four years, I've never had a scrut even look at my battery...much less weigh it.

Gary R.

No, but i'm bringing a scale to weigh Streak's battery at the next race!

wgn

The key to making these small batteries work is to be diligent about:

• Using the kill switch when the car sits (even overnight at a race or when trailering)
• Keeping it on a trickle charger between event

I've used a Braille 15 lb battery for a number of years. The only thing that has ever killed one of mine is having the car sitting at a shop that will not follows those rules...

Charles Kline

Just an update. The V2 Chillout System has an amp draw of about 18-20 amps when ducted with air from outside the vehicle. Max amp draw is at 22 amps if the system is operating at temperatures around 140 degrees which is unlikely. The version 1 would see about 22-24 amps max and 28 amps at 140 degrees which is the maximum operating temperature.

Happy to help with any questions you may have about Chillout and their systems.

Charles Kline

Just an update. The V2 Chillout System has an amp draw of about 18-20 amps when ducted with air from outside the vehicle. Max amp draw is at 22 amps if the system is operating at temperatures around 140 degrees which is unlikely. The version 1 would see about 22-24 amps max and 28 amps at 140 degrees which is the maximum operating temperature.

Happy to help with any questions you may have about Chillout and their systems.

spg993tt

seems to me, htats a lot of amps. and while the battery probably can take it, its drawing a lot of juice and probably starts to impact power a smidge. dont most SPBs have to add some weight to meet minimums. i think my car has 30,40lbs of ballast in it? it would be great if chillout had a battery pack option for their thing since, atleast for spbs, it might be a useful alternative to lead plates.
one of my kids had a leg injury and they prescribed andi bought a cooling system called "Game ready" google it. pretty nice system, same concept as the rest. they have a chest type thing for cooling and while designed for motorspors, the concepts are all about the same. they have a battery pack. id be concerned with it rattling itself apart having not been built for motorsports use. but i guess the point is, a battery pack option might be great. or a 15lb braille battery and an inverter...then, no draw from main battery.