What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Battery Mounted to Firewall

ColoradoSolar

Well Known Member
Hear me out, I am thinking about using 1 or 2 EarthX batteries in the 10 I am building and I know they should be behind the baggage bulkhead in the battery tray but I am going to have A/C in my plane and I don't want the tail to be too heavy. I will run some cg calculations before I make the final decision.

I was thinking about mounting the 1 or both batteries on the firewall, however since the heat in the engine is bad for the batteries I was thinking about mounting on the aft side of the firewall like what is in my 6A. This would provide many benefits like shorter cables for less weight and voltage drop. The aft side of the firewall would be much cooler and better for the batteries. Help to keep the cg forward with the A/C in the back. A downside is that they will be harder to get to even though I will have the access panel kit.

Has anyone ever done anything similar? I couldn't find anything in my search.
 
We have

Hear me out, I am thinking about using 1 or 2 EarthX batteries in the 10 I am building and I know they should be behind the baggage bulkhead in the battery tray but I am going to have A/C in my plane and I don't want the tail to be too heavy. I will run some cg calculations before I make the final decision.

I was thinking about mounting the 1 or both batteries on the firewall, however since the heat in the engine is bad for the batteries I was thinking about mounting on the aft side of the firewall like what is in my 6A. This would provide many benefits like shorter cables for less weight and voltage drop. The aft side of the firewall would be much cooler and better for the batteries. Help to keep the cg forward with the A/C in the back. A downside is that they will be harder to get to even though I will have the access panel kit.

Has anyone ever done anything similar? I couldn't find anything in my search.

We have done exactly what you are contemplating, but for a different reason. We also have A/C, but the bigger issue for us was an O2 bottle located where the battery tray normally is on an RV-10. We really didn't want a battery (of any chemistry) right next to the oxygen bottle. Don't know if the concerns were valid, but that was the choice we made.

Two ETX-900VNT batteries mounted on the sub panel (between the sub panel and firewall) with the Van's access panels on the forward fuselage skin. The venting of the batteries is down through the tunnel just aft of the firewall. Like you said, the cable runs are very short and we also mounted the four mil-spec contactors (Gigavac brand) on a tray in this same area.

I will say that access is not easy. To remove the battery (at least with the ETX900) requires the battery be lowered and removed under the panel - it does not fit through the access panels. Even though we have not flown quite yet (getting really close), I have on a couple of occasions already regretted this choice. That being said, I have had to connect and disconnect the batteries numerous times, which will (hopefully) be much less frequent once we are flying.

Email me if you want and I can send you some pictures when I'm back at SAS working on the plane.

krea dot ellis at gmail dot com
 
Your RV will not be tail heavy with AC. When I’m alone in mine, i frequently have additional ballast in the baggage compartment.
 
Your RV will not be tail heavy with AC. When I’m alone in mine, i frequently have additional ballast in the baggage compartment.

Do you have A/C in yours?

I am not worried about having to carry some ballast with just me or just 1 passenger. What I want to be able to do is carry 4, load it up to gross and still be in CG.
 
Back
Top