I just posted a 6th YouTube video featuring LocoFi in a Dead Rail/battery powered operation.
The New Video is Titled:
Making and Using a Portable Dead Rail Demonstration HO Layout - Part 6
Part 6 explains why the 3S LiPo powered Dead Rail conversion was changed to use a trailing battery car for an IMR Lithium-ion 3S 350mAh pack, and why it is a “better” way to convert to Dead Rail in HO scale locomotives. The LocoFi™ system was used for locomotive control and sound for this battery powered, Dead Rail, conversion.
My Webpage has a lot more information on this and related topics.
It is titled, “A Journey Into HO Scale Model Railroading in the 21st Century”.
The page has been updated and contains information that is NOT in the YouTube videos. It also contains information that has has been garnered since the videos were posted, including several corrections. At times, there is also information on the Webpage that I have not shared on YouTube yet.
It was fun to put the two Dead Rail Converted LocoFi™ controlled locomotives on the layout and run them together with their battery cars. The low speed capability of the LocoFi™ decoder still amazes me.
Soppy, I loved your “thinking outside the box” idea of using the track to connect the battery car to the locomotive. As you yourself, as well as a couple of others have noted, that could be problematic at times, but the thinking outside the box and sharing it was fantastic! That is what I’ve been trying to do, get folks “thinking” and bouncing their ideas off each other.
For more capacity, for either a longer prototypical run time or when powering locomotive consists, as we now have some excellent ideas of how to consist locos with a trailing battery car, I have procured some IMR 14500 LiMN cells and 3S (series) AA battery boxes. Yes, they do make 3S AA battery boxes and the 14500 Lithium cells are, for all practical purposes, the same physical size as AA dry cell (primary cell) batteries.
The weight difference between the 4S 10440 battery pack, with 3 cells/batteries in the circuit and one “rider” and the 3 14500s in their single 3S pack is only 20g or a little less than 3/4 of an ounce. The AA battery boxes are just a tad under 6-1/4” inches long (measured) and easily fit on the floor of the gondola and boxcar.
While I now have the 14500 cells/batteries and the 3S AA battery boxes, I’m not ready to swap them in yet and give them a try, as I’ve eliminated the connector between the loco’s and their trailing battery cars.
I’m thinking of ordering the MicroMark connectors that John Holdos mentioned in the Parallel Consist Wiring thread and give them a try.
When I removed the connector, that I had used, for the Conrail conversion with the gondola battery car, using the 3S 10440 battery pack and then reconfigured the locomotive in the App, it appears that the voltage went up, as during the reconfiguration, the Step 7 speed went up from the original 65 mph to 72 mph, compared to when the connector was in the circuit.
At this point, I am encouraged to note that the 6th video in the series is getting a bit of traction on YouTube, but I am disappointed that there have been no other Dead Rail videos posted recently on YouTube. There just has to be others “out there” doing Dead Rail with LocoFi and the other available systems.
At the moment I am looking into how battery protection circuits (BPC) or battery management systems (BMS) can affect the depth of discharge (DoD) of Lithium based cells. Once the cell “knees” over, there is not a lot of useful capacity left in the cell, and draining the cell well below the “knee” puts it into a deep discharge situation. Adding a DC to DC converter, either up or down, along with a BPC or BMS exacerbates the situation as it disguises how far down the cell or battery is actually being drawn.
The effect of a high DoD on lead acid batteries is well known and understood, but there are varied opinions on the effects of high depths of discharge on Lithium based batteries. Most “experts” agree that high depths of discharge, on Lithium based batteries, do cause serious capacity loss.
There is always so much more to learn and I am very surprised that more research has not been done in this area of model railroading.
Although a novel approach to feed power to the tracks from the battery car, the locomotive is now essentially "track powered" and "NOT deadrail" anymore. We could as well not use a battery car at all and simply "power the tracks" from a high amp "always on" regulated DC supply. Ironically, we have a similar video on our website titled LocoFi™ - Demo Run on 9V Battery that simply demonstrates that we can also use a battery to power the locomotive but essentially the battery is feeding the tracks (no battery car though).