Saving (Lots) of Weight with a Pegasus Racing Ballistic Battery

by Mike Kojima

“No way is this thing gonna start the car” is the first thing we said when we opened the box containing the Ballistic Battery we had purchased from Pegasus Racing. Even though the tech guys at Pegasus had assured us that this battery could easily start and run the big 8 liter Chevy engine in one of our race cars, when we hefted it's 6.5 lbs, we knew that there was no way it could!

Looking at the batteries specs, we could see that the Pegasus battery had an incredible 1000 MCA cranking amps. This is different than the CCA spec listed for lead acid batteries as CCA is tested at zero degrees F and this rating is tested at 32 degrees F. Pegasus feels that the temperature is a moot point since these batteries get warmer as they discharge so at zero degrees, the batteries core temperature would rise to about 70 degrees in a few seconds.

The battery has a capacity of 20 amp hours which is more than the 16 amp hours of our old low electrical load race car standby, the Odyssey 680 and twice it's cranking amps when measured at 32 degrees as per MCA. It is less than half the weight as well!

This is the bad ass Optima Yellow top that was powering our race car. We chose the yellow top because we wanted dead nuts reliability from our charging system under any condition. The Optima weighs in at 44 lbs on our scale. It has 870 MCA cranking amps and huge 55 amp hours of capacity. By changing batteries we saved a whopping 37.5 lbs! Would our new battery survive in a race car environment? We think so.

We fabbed up this secure battery box and welded it to the cage and chassis in several places opposite of the driver and in front of the dry sump tank. Secure battery mounting is often ignored and critical for safety.

The Pegasus Ballistic battery uses a Lithium Iron Phosphate chemistry. This is a new variant of the common Lithium Cobalt Peroxide lithium ion batteries found on nearly anything that needs a rechargeable battery. Lithium Cobalt Peroxide lithium ion batteries are somewhat new to the motorsports world coming out as a super light weight replacement for the traditional sealed high density lead acid or gelled electrolyte battery that has been used in motorsports for years.

Lithium ion batteries have a very high power density and the ability to take multiple charge cycles. Their high power density means that they can be about half the weight of the traditional lightweight motorsports battery which is again about half the weight of the big lead acid battery in your car.

The battery fits in the box like so. Previously the battery was behind the driver. By being compact, the new battery can fit on the passenger side improving the weight distribution considerably. This was easy to see on the corner scales.

The Pegasus LiFePO4 battery chemistry offers many advantages over other batteries including other types of lithium ion batteries. It has a longer cycle life than most other batteries. It has a very constant discharge voltage, meaning it's voltage will stay high and stable until the battery is totally exhausted. It has a higher peak power rating than other chemistries. It can also charge quickly.