Lithium Batteries and battery boxes

[bigjae1976]

I have a 2004 BMW M3 and the battery is located in the passenger area so I need a battery box. Is there a specific spec that a battery box needs to meet? The CCR says to use a marine battery box. Probably needs to be non-conductive (duh) but does it also need to be water tight? Or does it need to be fire resistant in the case of lithium? 

I believe lithium batteries need to be vented for temperature control. What about a vented box?

[Hank P.]

Hi, quick recap of the CCR rules re batteries and then I can answer your questions:

For HPDE and TT: 11.4.9 Battery
The battery should be securely fastened to the car. No Bungee cords or rubber cords may be used to function as the sole hold down mechanism. An electrically non-conductive material should cover the positive battery terminal. Any battery located inside the driver’s compartment should be fully covered and firmly secured to the chassis (or tub) in a marine type battery case. Dry cell, gel cell, and AGM batteries may be mounted without a surrounding case however a case is still recommended. Lithium ion batteries must be outside of the passenger area of the vehicle. Note- a ruptured lithium ion battery is subject to instant ignition at such high temperatures, the owner/ builder runs the risk of the entire vehicle being consumed by the fire.

For Race: 18.5 Battery
The battery should be securely fastened to the car. No Bungee cords or rubber cords may be used to function as the sole hold down mechanism. An electrically non-conductive material must cover the positive battery terminal. Any battery located inside the driver’s compartment shall be fully covered and firmly secured to the chassis in a marine type battery case. True dry cell and AGM type batteries may be mounted without a surrounding case. Lithium ion batteries must be outside of the passenger area of the vehicle. Note- a ruptured lithium ion battery is subject to instant ignition at such high temperatures, the owner/ builder runs the risk of the entire vehicle being consumed by the fire.

Also, please note this clarification from the NASA National office re Lithium Iron Phosphate batteries: "The CCR is very clear about Lithium Ion batteries. Lithium Iron Phosphate batteries are different and not specified. While caution and common sense should always be used, there is no indication in the CCR that the Lithium Iron Phosphate batteries cannot be treated like all other batteries."

So:

Per the CCR a Lithium Ion battery must be mounted outside of the driver/passenger area, regardless of the use of a box.

Per the NASA National office a Lithium Iron Phosphate battery may be mounted inside the driver/passenger area but must be in a box.

All that said, here are responses to your questions:

There is no spec for the battery box. The CCR does not require that the box be water-tight or fireproof, and many marine-type cases are not completely sealed. For your safety the box should be able to stop or slow the spillage of corrosive or flammable materials from the battery. Best practices suggest a sealed fire-resistant box that is vented to the outside. Again, per the NASA National office, caution and common sense should always be used.

Hope this helps; lmk if you have any other questions. In which region are you located?

 

[bigjae1976]

I’m in TX. I have a battery tender lithium battery...looks like it’s a LiFePo.

The battery is in the trunk. I have no bulkhead or rear seats. Is the trunk considered the passenger compartment?

[Hank P.]

With no bulkhead or rear seats, the trunk is considered part of the driver/passenger compartment since it is open to the driver capsule. So, a box will be required.

[bigjae1976]

Got it. Thanks!

[Hayden25]

On 2/12/2021 at 2:15 AM, Hank P. said:

Hi, quick recap of the CCR rules re batteries and then I can answer your questions:

For HPDE and TT: 11.4.9 Battery
The battery should be securely fastened to the car. No Bungee cords or rubber cords may be used to function as the sole hold down mechanism. An electrically non-conductive material should cover the positive battery terminal. Any battery located inside the driver’s compartment should be fully covered and firmly secured to the chassis (or tub) in a marine type battery case. Dry cell, gel cell, and AGM batteries may be mounted without a surrounding case however a case is still recommended. Lithium ion batteries must be outside of the passenger area of the vehicle. Note- a ruptured lithium ion battery is subject to instant ignition at such high temperatures, the owner/ builder runs the risk of the entire vehicle being consumed by the fire.

For Race: 18.5 Battery
The battery should be securely fastened to the car. No Bungee cords or rubber cords may be used to function as the sole hold down mechanism. An electrically non-conductive material must cover the positive battery terminal. Any battery located inside the driver’s compartment shall be fully covered and firmly secured to the chassis in a marine type battery case. True dry cell and AGM type batteries may be mounted without a surrounding case. Lithium ion batteries must be outside of the passenger area of the vehicle. Note- a ruptured lithium ion battery is subject to instant ignition at such high temperatures, the owner/ builder runs the risk of the entire vehicle being consumed by the fire.

Also, please note this clarification from the NASA National office re Lithium Iron Phosphate batteries: "The CCR is very clear about Lithium Ion batteries. Lithium Iron Phosphate batteries are different and not specified. While caution and common sense should always be used, there is no indication in the CCR that the Lithium Iron Phosphate batteries cannot be treated like all other batteries."

So:

Per the CCR a Lithium Ion battery must be mounted outside of the driver/passenger area, regardless of the use of a box.

Per the NASA National office a Lithium Iron Phosphate battery may be mounted inside the driver/passenger area but must be in a box.

All that said, here are responses to your questions:

There is no spec for the battery box. The CCR does not require that the box be water-tight or fireproof, and many marine-type cases are not completely sealed. For your safety the box should be able to stop or slow the spillage of corrosive or flammable materials from the battery. Best practices suggest a sealed fire-resistant box that is vented to the outside. Again, per the NASA National office, caution and common sense should always be used.

Hope this helps; lmk if you have any other questions. In which region are you located?

 

That explains it. My buddy is looking to place a battery at the passenger side as well on his new M3 project. We'll work on it after we finished installing the new set of tires from 4Wheelonline on the truck.