Sojourner1
Itinerant
As a fulltimer living off lfp/ solar not being able to charge the batteries could be an issue as I recently found out.
I'm thinking here of adding a 12v heating pad under my battery bank in the rv. This will be a backup for if it really gets cold or one of the heating sources for the compartment goes south. We all know that lfp batteries shouldn't be charged below 32°f and with my batteries the EMS will shut charging down if any of the 20 prismatic cells do drop below 32°f, after 44 months we were in extreme cold and couldn't move from it like we normally would do.
I have no experience with this pad maybe someone else does or installed something similar. It has a built-in thermostat that is set to turn itself on at 45°F( + - 5 degrees) and turn itself off at 68°F( + - 5 degrees). As long as the on/ off switch is in the on position.
This is what I'm thinking of using...
Facon 12v heating pad 7.5" x 25"
These are sitting directly on the metal floor of the compartment and the furthest cells (17-20) can be 4°f colder than other cells (I can see all individual cell temps/ voltages). I can raise the batteries about 1 inch. My thought is to pull the batteries out of the enclouser their in (keeps them moving) putting 1/4" piece of plywood on the bottom (maybe a thin piece of solid foam insulation under it), piece of felt on the plywood top, the heating pad normally would get stuck to a plastic holding tank/ water tank I was thinking of getting a piece of aluminum and sticking the pad to the bottom of it to tansfer the heat better, then putting a piece of felt on the top of aluminum with the batteries on top of that.
Looking like this...
Batteries
Felt
Aluminum sheet
12v Heating pad
Felt
1/4" plywood
(Maybe) Thin foam insulation
Metal compartment floor
The heating pad can be connected to the 12v fuse panel with a switch added inline to turn it on/ off if needed. Power consumption should be roughly 6a which would be a little more than 1% an hour of my battery bank, I'm thinking it probably wouldn't need to be used more than an hour or so periodically.
Using 12v instead of 120v saves the lose of converting from the inverter. The only thing that I'm thinking about is with the built in temp on the heating pad will it be turning itself off because it will be within the sandwich under the batteries and not in an open air space of holding tanks?
Opinions? Critique? Thoughts?
I'm thinking here of adding a 12v heating pad under my battery bank in the rv. This will be a backup for if it really gets cold or one of the heating sources for the compartment goes south. We all know that lfp batteries shouldn't be charged below 32°f and with my batteries the EMS will shut charging down if any of the 20 prismatic cells do drop below 32°f, after 44 months we were in extreme cold and couldn't move from it like we normally would do.
I have no experience with this pad maybe someone else does or installed something similar. It has a built-in thermostat that is set to turn itself on at 45°F( + - 5 degrees) and turn itself off at 68°F( + - 5 degrees). As long as the on/ off switch is in the on position.
This is what I'm thinking of using...
Facon 12v heating pad 7.5" x 25"
These are sitting directly on the metal floor of the compartment and the furthest cells (17-20) can be 4°f colder than other cells (I can see all individual cell temps/ voltages). I can raise the batteries about 1 inch. My thought is to pull the batteries out of the enclouser their in (keeps them moving) putting 1/4" piece of plywood on the bottom (maybe a thin piece of solid foam insulation under it), piece of felt on the plywood top, the heating pad normally would get stuck to a plastic holding tank/ water tank I was thinking of getting a piece of aluminum and sticking the pad to the bottom of it to tansfer the heat better, then putting a piece of felt on the top of aluminum with the batteries on top of that.
Looking like this...
Batteries
Felt
Aluminum sheet
12v Heating pad
Felt
1/4" plywood
(Maybe) Thin foam insulation
Metal compartment floor
The heating pad can be connected to the 12v fuse panel with a switch added inline to turn it on/ off if needed. Power consumption should be roughly 6a which would be a little more than 1% an hour of my battery bank, I'm thinking it probably wouldn't need to be used more than an hour or so periodically.
Using 12v instead of 120v saves the lose of converting from the inverter. The only thing that I'm thinking about is with the built in temp on the heating pad will it be turning itself off because it will be within the sandwich under the batteries and not in an open air space of holding tanks?
Opinions? Critique? Thoughts?