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  • #16
    Anyway, about that battery location... Has anyone built trays to secure their lithium batteries in a horizontal orientation?

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    • #17
      The company name is E-Mag Electronic Ignitions (link).

      Their electronic ignition products are the P-114 (for 4-cylinder Lycoming and Continental) and P-200 (still under development for 6-cylinder Lycoming and Continental). They also sell ignition harnesses and automotive-type spark plug adapters for use with their electronic ignition system, along with drive gears for those engines that require them.

      I have only discussed experimental use of their products, but I know they have been trying to get them through FAA certification - just don't know the results of those efforts (wasn't on my radar). I believe they clearly "misunderestimated" (quoting GW Bush) the complexities of dealing with the FAA to certify something like this...
      Jim Parker
      Farmersville, TX (NE of Dallas)
      RANS S-6ES – E-LSA powered by 100 HP Rotax 912ULS

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      • #18
        Does anyone have photos showing the starter cables where they penetrate the firewall ? I’m trying to get an idea of the cable size and to understand the concept of getting them through the firewall. Any photos would help. Thanks.
        Nev Bailey
        Christchurch, NZ
        Builders-log
        YouTube

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        • #19
          Also......

          If I go with mounting the battery under the front right seat, are there any issues with running cables down through that floor panel ? Is it relatively straight forward? Any pros and cons with the battery orientation? I figure that if I put the battery on the far right side under the seat it will be sitting directly over a cross-tube for support, with another cross-tube in front. Having it face sideways or rearward gives easy access for removal etc.

          Thanks.

          45EC3E2B-12EE-4C20-8C32-8BDE971FBB61.jpegB812D2D6-70C9-4034-B511-AE2BA4058FA8.jpeg
          Nev Bailey
          Christchurch, NZ
          Builders-log
          YouTube

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          • #20
            I used electrical bulkhead fittings to penetrate the firewall. I’ve never liked un-fused high load wires going through bulkheads/firewalls with only a rubber grommet for protection. Obviously it works because that’s how it’s done in aviation but I chose to use fittings. See the red lugs on the far side of the firewall.

            1C89F057-837B-48B6-9DFE-2894E83C79CB.jpeg
            Scratch Built 4-place Bearhawk. Continental IO-360, 88” C203 McCauley prop.

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            • Nev
              Nev commented
              Editing a comment
              Thanks Whee !

          • #21
            Under the right front seat is where the battery is in my four place. I had an Odyssey 680 forever until a few months ago when the second or third one went bad, and I replaced it with the 900 series from Earth X. You do want to be able to remove it. And you do want to be able to access it with charger cables if it needs charging. Mark

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            • #22
              I like the firewall. If you keep the leads short you can get away with #4 cables. Under the seat you will probably need #2, and 3 or 4 times more of it. A couple pounds?

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              • #23
                Originally posted by svyolo View Post
                I like the firewall. If you keep the leads short you can get away with #4 cables. Under the seat you will probably need #2, and 3 or 4 times more of it. A couple pounds?
                Did you vent your battery to keep the temps in check out of interest?
                Nev Bailey
                Christchurch, NZ
                Builders-log
                YouTube

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                • svyolo
                  svyolo commented
                  Editing a comment
                  I have the same battery and box as you have. I am going to put a very small (8-12 mm) tube and ventilate it from the cowling. Not really to cool it, but to keep hot air out. I will start out with a temp sensor to make sure it works. The cold side of the firewall would be my second choice, and a close second.
                  Last edited by svyolo; 02-23-2021, 08:54 PM.

              • #24
                For a conventional aircraft layout, I like the firewall for ease of maintenance, short cables, less weight and simplicity. I would only mount it elsewhere for CG reasons. If it were a lithium, I'd never put it in the cabin. My background includes qualification testing of lithium aircraft batteries and after watching a battery under test fill a room with toxic fumes in seconds, I'm not willing to take that chance. It's unlikely that a battery in a real world environment will experience a failure like that, but when I have other options, I'm going to choose the other option.

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                • Nev
                  Nev commented
                  Editing a comment
                  Thanks David, appreciate your view.

              • #25
                Originally posted by David Swartzendruber View Post
                For a conventional aircraft layout, I like the firewall for ease of maintenance, short cables, less weight and simplicity. I would only mount it elsewhere for CG reasons. If it were a lithium, I'd never put it in the cabin. My background includes qualification testing of lithium aircraft batteries and after watching a battery under test fill a room with toxic fumes in seconds, I'm not willing to take that chance. It's unlikely that a battery in a real world environment will experience a failure like that, but when I have other options, I'm going to choose the other option.
                The issue with EarthX lithium batteries is they do not have the temperature rating required to be installed on the engine side of the firewall, ie the engine side is too hot. I agree though, they should be put in a sealed/vented to outside box.
                Scratch Built 4-place Bearhawk. Continental IO-360, 88” C203 McCauley prop.

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                • David Swartzendruber
                  David Swartzendruber commented
                  Editing a comment
                  Yes, a good location for a lithium can be challenge. I looked on the EarthX website and they provided this statement under the heading of Important Safety/Use Precautions: "Only the ETX900-VNT is designed for in cabin installations as it has a venting system build in and is also in a fire proof containment system."

                • jaredyates
                  jaredyates commented
                  Editing a comment
                  I run the earthx on the hot side of the firewall. While it would be nice to have a higher temp rating, the temp rating is higher than the PC680 SLA that I also ran on the hot side of the firewall.

                • whee
                  whee commented
                  Editing a comment
                  Jared, I had never looked up the PC680 temp rating since they are so commonly used. Your right, the Earth X is rated at 140F and the 680 at 113F. The SBS J16 (certified version of the 680, metal jacket) is rated at 176F.

              • #26
                I did a very quick calculation a year or two ago. Mounting a battery aft for CG change isn't the most efficient solution to shift the CG. Upsizing the wiring diameter and extra length, and most of that wire weight isn't helping the CG that much as it is spread from the starter to the battery. It is more efficient, with respect to added weight, to just mount weight in the tail.

                I think the LifePO4 batteries are pretty safe, but just the thought of having a battery fire right under the family jewels has me thinking of a different location.

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                • #27
                  I worked on this yesterday!!

                  The Patrol's Firewall Real-estate is smaller than a side-by-side aircraft. The Battery placement cant be behind a Mag, or governor, or impede the engine control cables. The engine mount is the largest factor that eliminates a host of places. Battery placed down near the Hot Exhaust did not seem ideal to me.

                  IMG_2321 2.JPG

                  I decided the inside firewall, up high. Placing both the relays and the battery there keeps the engine side of the firewall clean. I will have the side panels of the boot cowl removable so serving the relays and battery is reasonable.
                  IMG_2322.JPGIMG_2323.JPG
                  Last edited by Bcone1381; 02-24-2021, 12:24 PM.
                  Brooks Cone
                  Southeast Michigan
                  Patrol #303, Kit build

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                  • #28
                    Nev, consider the bend radius of the wire you use. You can buy #2 or #4 welding cable on EBAY, it is much more flexible than aircraft cable, thus much easier to use. Looks like you can go straight down through the floorboards, make sure you protect the wires going through the floorboard. I really like Whee's bulkhead electrical fittings. I'm still on the fence on which side of the firewall to locate the EarthX 900 battery. Sometime ago someone on the list reported that their EarthX battery on the firewall swelled. Not sure if it was from heat, they were sending back to EarthX. Worst time for heat is after shutdown, no cooling available from airflow.

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                    • #29
                      I worked on this yesterday!!
                      Brooks, thanks for the detail and ideas. This looks a very neat installation.

                      I’ve been considering this location also. I guess on the Patrol you will bring the Throttle/Mixture cables through the left side of the firewall. On the 4-place I think they’ll need to penetrate the firewall close to the center and near where your battery is mounted. Incidentally I’m using the Vertical Power PPS as a solution for contactors etc. I’ll post some pics of it later.
                      Nev Bailey
                      Christchurch, NZ
                      Builders-log
                      YouTube

                      Comment


                      • #30
                        Nev, consider the bend radius of the wire you use. You can buy #2 or #4 welding cable on EBAY, it is much more flexible than aircraft cable, thus much easier to use.
                        Thanks! I’m planning to use welding cable, I think I can buy it at the local welding suppliers. I really liked Whee’s idea too and will visit the V8 racing supplier today, I think they’ll sell something similar. They’re also a great source of AN fuel/hydraulic hardware.
                        Nev Bailey
                        Christchurch, NZ
                        Builders-log
                        YouTube

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                        • Bcone1381
                          Bcone1381 commented
                          Editing a comment
                          I used welding cable purchased at my local welder. I cooked a piece of wire in a turkey roaster to test its resistance to heat. 350F for 1 hour was no problem. At 450F the rubber insulation was still very sound, but the paper that is between the insulation and the copper wire started to discolor and smoke a little bit. I thought that was very acceptable, but am open to hearing if anyone thinks otherwise.
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