When I bought the bus I new the original battery tray would have to be replaced. The folks who owned the bus before sold it with a tiny car battery instead of the large truck 4D size it is supposed to have. Part of the reason for that I expect was the tray rusting out.. and the fear of it not being able to support the 97lb 4D.
I had the same thoughts, and although I had already bought the proper battery long ago, I figured having the right battery in stock would help with designing a new tray. Which it did since this involved a lot of research and angst. I went with Stainless Steel for the new tray. That causes potential issues with galvanic corrosion between the steel sliding extension rails and the stainless steel. This combination was within my risk limits based on a lot of research, and we started the design. I’ll be checking the screws into the rails often though for corrosion as they are the weak point.
I have a really talented young man who is doing metal fabrication for me as needed. He took the original tray and reproduced it in stainless, including very well matched holes to bolt it to the rails. One of things lacking on the original were a good way to secure the battery from bouncing up off the tray with large bumps. So we added in threaded rod and a cross brace to hold it down.
We also added in additional drain holes and I mounted HDPE blocks to keep the battery from shifting side to side. These blocks are raised slightly above the tray bottom to allow any water to free flow to the drains. The battery also now sits on a thin urethane pad as well. That helps isolate it some from freezing temperatures.
Taking out the old tray, cleaning decades of gunked up grease and grime from the rails, and getting the screws out was a major choir. Whoever designed the original tray, rails and mounting points I guess assumed it was never coming back out. After many days of fighting with it, cursing up a storm, and creating a lot of improvised special tools, I got it out. Rinse and Repeat to install the new tray. Sheesh.
At this point I have added in a RuuviTag Pro 2in1 Wireless Bluetooth Temp and Motion Sensor to the outside of the tray to report outside air temperature to the central Victron Cerbo GX for System Monitoring and Control.
As a separate management system, the battery has a Victron Smart Battery Sense, Voltage and Temperature Sensor mounted directly to it with an adhesive pad. This remote sensor links to the Victron Blue Smart IP22 Smart Battery Charger providing 12V at 30A, for Float & Trickle Charging and managing the battery charge when not in motion.
In motion, I am using a Victron Energy Orion XS Smart DC to DC Battery Charger 12/12 50A (700W) to provide charging to the Epoch Batteries 920 amp/hr House LiFePO4 Battery bank.
Still to be done, I need fabricated a small bracket attached to the battery hold down. This bracket will be the mounting point for a 3/8″ Stud 40 Amp Circuit Breaker that connects to the Victron Blue Smart charger and Orion XS DC to DC charger.
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