1-800-221-9425 | Call the Aircraft Parts Experts
Home/Firewall Forward Parts/Batteries/EarthX Batteries/BB-TH-CO THERMAL BATTERY BOX “C” CASE


Out of Stock


Thermal battery box to protect from radiated or convection heat!

The EarthX thermal battery box is designed to protect the battery in engine compartment installations from periods of high temperature (up to 1 hour), such as after shutdown, and from radiant heat from hot surfaces like exhaust systems during and after flight. This stainless-steel box has a mirror finish to minimize the effect of radiant heat, and it has a high-performance insulating foam layer between the box and battery to reduce effect of convection heat.  This battery box was engineered to be strong enough to withstand 30 G of force yet only weighs 1 pound.

All batteries have optimal temperature ranges for use in operation. The ETX hundred series is rated for 140 deg F ( 60 deg C) or less for optimal longevity and performance of the battery. Typical lead acid batteries are rated to 113 deg F or 45 deg C.

This battery box is designed to be compatible with our existing “C” case battery models; ETX680C.

SKU: BB-TH-CO Category:



The “Radiant and Convection” graph shows the internal cell temperature with an extreme test example.  The battery was placed in a test environment chamber with temperatures of 185 Deg F (85 deg C) and simulated 1000 Deg F (538 deg C) exhaust pipe 6 inches from the front of the battery.  In this case there was a 3.5X improvement in the time to heat up the battery cells to the high operating limit.  In less extreme temperatures, the improvement can be 4X.

The “Convection” graph shows the battery (not cell) temperature rise with a test environment of 185 Deg F (85 deg C).   In this case there was a 5.3X improvement in the time to heat up the battery.

ETX Battery Box Installation Guide


This document provides recommended guidelines for the installation of EarthX battery boxes.

Number of Required Fasteners

The table below shows the recommended number of fasteners to be used when securing the battery box to a vertical surface, like the engine firewall. The number of fasteners is based on ASTM 2245 6g upward force, plus a 1.5X safety factor (9g downward or upward). The battery weight used in the calculation was the ETX900 (4.9lb).

The material the box is fastened to should be of equal or greater strength than that of the battery box (14ga aluminum or 22ga stainless steel).

Fastener Type Quantity (minimum, total)
1/8” rivet 4
10-32 screw 4
¼-20 screw 4

Fastener Location

Ideally, the fasteners should be located at the four corners (blue dots) as shown below. Based on the build of the aircraft or battery location it may not be possible to locate fasteners uniformly at the corners or in all the pre-drilled holes provided on the battery box. All that is required is to install a fastener on the top 1/3 length of the support tab and another on the lower 1/3 as shown below. Additionally, the fastener hole should be located at least 1-hole-diameter from the edge of the support tab.