On board battery recommendations

[JHerscher]

In need to buy an onboard battery. I'm looking for recommendations, taking into account size, durability to vibration, longevity (how long before I need to replace), capability of multiple unassisted starts, and weight based on the requirements outlined below. I am aware that in the last several years there have been strong advances in lighter weight batteries, and I'd like to take advantage of that if possible.

My last battery was a Varley. Lasted over 8 years (possibly longer - it came with the car when I bought it in late 2012) so I am happy with the performance of Varleys and will likely go that route unless a better alternative is identified.

Car: Van Diemen RF01 FC
Pinto (total loss)
Maximum size (same as Varley Red Top 15) - 8" L x 3" W x 5.5" H
Padding at bottom of battery box is 1/8" thick rubber sheet glued to the floor. Clamp is spring loaded and padded. No space for additional padding.

I start the car at my pit on a jumper battery before belting myself in, but would like to have the ability to start without a jumper 5-6 times a day as I am a one-man show and would need to start on the grid each session.

My experience with Odyssey batteries has not been good - it may be due to the vibration. I had one fail and leak during a race, and the other just stopped holding a charge after about a year. It may just be bad luck but I'm wary of them now.

Size can't be any bigger; those who have met me know that I am not your typically sized formula car driver. Lighter is also better. If the size is small enough, I'd consider two small lighter batteries in place of the single if that would get me the desired starting performance.

Thanks for the input

John

[mikey]

Given that you have a total loss system, the answers to your questions and hope for eliminating the need for a jump box really depend on your total energy requirements.
How much energy does your system consume in a day of racing? Include measured draw during cold start as well as during racing.

given your dimensions stated, 15Ah is the approximate reserve capacity available, which is not enough to do that many starts on a total loss system I don't think.

Whatever you choose, I'd get away from lead-acid. Go at least AGM (my preference) or Lithium if you can afford it and it suits your needs.

[DaveW]

My battery is an East Penn (DEKA) ETX-18L AGM (20 AH) which I charge as often as possible at the track.
That has plenty of power for starting my Zetec w/o a jumper battery. It should also work well in a total-loss Pinto-engined car.

Unfortunately it's a few tenths of an inch bigger in all dimensions than what you had. It weighs ~18 lb.

Link: https://www.googleadservices.com/pag...gQIARBh&adurl=

Free pickup at Lowes, which is where I got mine.

[Rick Kirchner]

john:

I have been down the same route as you. Varleys are great, but $$$ and heavy. They also do not like getting hit with a surge - like when you attach a jump battery. They like low rates of charge.

I've had no issues with the Odyssey's but replace them at 3x the rate of the varleys.

IMHO, jump batteries are always a bad idea. If your onboard can handle the surge, OK, but if for some reason your jump battery is low you'll drain the onboard when you hook up.

My system is set up so that if the master sw is off you can hook up the jump battery and run the whole car but the onboard is isolated. I warm the car up for ~20 minutes before a session, disconnect the jump, turn on the master and it fires right up without any strain on the onboard system.

[Motorsport Services]

Odyssey PC 680 AGM. $130 from Amazon.

[Farrout48]

John - I have been using an AntiGravity Lithium Battery AG1601. I do have the GSXR charging system rather than a total loss system. Weight is 3.18#. I only put it in this winter after my voltage regulator failed and put 20 amps into the Ballistic battery that was in the car. I had been using Ballistics Lithium batteries (no longer available) for years but usually got 4 years life out of them. They are a bit pricey ($239) but I needed the 10# weight savings. The AG 1601 is smaller than what you mentioned except that the width is 3.25".

When I was looking at their website just now, I saw a new model called the JumpStart Battery. It has a reserve start button to provide a boost when the battery had gone to low charge level. I do not know how that might work for your total loss system.

[Pi_guy]

I will get a lot of flack for this I am sure but it has worked for me.
With the cars I ran I never had a DNF due to a battery.
My rule was new battery every year. I carry this over to my boat I change the bank of batteries every year.

Boat batteries like formula car batteries used on weekends, not used for stretches of time subjected to pounding. Both are basically abused the old saying pay me now or pay me more later fits.

[BeerBudgetRacing]

Odyssey PC 680 AGM. $130 from Amazon.

Look for the -MJ. Metal jacket. Helps with vibrations.

[jrh3]

Odyssey PC 680 AGM. $130 from Amazon.

I’ve used these on three race cars and three airplanes (360 ci) without a failure.

[Steve Demeter]

I have had a DEKA as Dave W described for going on 7 years. Runs a Pinto on a full drain. Charge it between sessions. Use a jump battery with master off to start. Last weekend had to start on track 5 or 6 times one session and no issue whatsoever. BUT: it is always important to long life and maintaining capacity to charge the battery on a regular basis. I like to do mine at least once a month on a slow charge til they are full. That includes tow vehicles, lawn mowers ,etc.

[EricP]

I will get a lot of flack for this I am sure but it has worked for me.
With the cars I ran I never had a DNF due to a battery.
My rule was new battery every year. I carry this over to my boat I change the bank of batteries every year.

Boat batteries like formula car batteries used on weekends, not used for stretches of time subjected to pounding. Both are basically abused the old saying pay me now or pay me more later fits.

I think this is good advice and do the same but sometimes go two years. The first time I kept the “old” battery rather than exchange it and so as I switch out the previous year’s battery it becomes a backup/start pack if needed.

[Pi_guy]

I think this is good advice and do the same but sometimes go two years. The first time I kept the “old” battery rather than exchange it and so as I switch out the previous year’s battery it becomes a backup/start pack if needed.

I have over forty years of following this rule. Not likely to change.
Now that I spend my time on the water it is more important to me not to have a battery issue.