Forward Battery Box

I am installing a dual-battery electrical system. The primary battery, an EarthX ETX900, will be installed in the standard location behind the baggage compartment. The second battery, an EarthX ETX900-VNT (the vented variant) will be installed under the subpanel.

A forward-mounted battery allows me to provide an unswitched battery bus for my electronic ignitions and injectors. I deliberately laid out my sub-panel components in such a way that this unswitched bus can be contained to a small area above the pedals on the co-pilot side. One of my design goals is to allow the engine to continue operating with the electrical system switches in the off position (the fire in the cockpit scenario).

I determined that I could mount an EarthX aluminum battery box below the sub-panel and above the Control Approach rudder pedals. I used two lengths of .063″ angle to suspend the box under the panel. I’ll use the forward portion as a shelf for mounting the fuse panel for the bus.

The battery box is bolted to the angle along with two lateral angles that hold the battery in place. The assembly is attached to the lower flanges of the panel/sub-panel with #6 screws, allowing the entire assembly to be removed.

I made a part from a UHMW block that secures the battery box to the rudder pedal crossbar. An adel clamp with a UHMW lining secures this around the bar.

The result is very solid and secure. The rudder pedals continue to move freely. The arm of the pedal clears the bottom of the box by over 1/4″ in the full forward position.

The box is positioned close to the firewall ground tie point. The fuse panel will be installed on the rails in front of the battery and the SDS components will be installed on the sub-panel above.