Lithium Iron Phosphate (LiFePO4) DIY battery heater - anyone make one?

[Yoda]

New brainstorm. Was reading an article on DIY RV automation and they mentioned using Bluetooth relays.

Could I use something like this https://www.amazon.com/DSD-TECH-2-Ch...21&sr=8-6&th=1 orhttps://www.amazon.com/DSD-TECH-Channels-Bluetooth-Compatible/dp/B07GFH5J96/ref=sr_1_3?hvadid=616862874444&hvdev=c&hvlocphy=90 29146&hvnetw=g&hvqmt=e&hvrand=17528884698021776045 &hvtargid=kwd-301163932733&hydadcr=24633_13611805&keywords=bluet ooth%2Brelay%2Bboard&qid=1674663921&sr=8-3&th=1

To control (power) the thermostat relay https://www.amazon.com/gp/product/B0...GOJR8LMXA&th=1 I wonder if it keeps its settings when powered off?

Still reading up on the Cerbo GX though. Edit - manual here https://www.victronenergy.com/upload..._Manual-en.pdf

Keith

Second Edit

I think I found how to wire additional temp sensors and have the GS activate heating pads through the programmable relays. Section 5.4 here https://www.victronenergy.com/media/...iguration.html

However I have not found anything on the amp rating of the Curbo Gx relays. Anyone have this information or know where to find it?
Third Edit - it appear to be 6A found here https://www.victronenergy.com/live/venus-os:start

Also the temp sensors are made to connect to something https://www.victronenergy.com/access...a-pmp-venus-gx I have one connecting the multiplus to the negative battery terminal per instructions, but none connected to the Cerbo GX yet. Will they work just suspended in a case (taped to a battery)?

Thanks

[acoleman43]

You mean you want me to read up on how to get the Cerbo to activate the heating pad and build something before you do?????????? Ill haft to think about that

Keith

Yes. You work out the bugs, we all benefit from your knowledge

[Yoda]

Yes. You work out the bugs, we all benefit from your knowledge

Yep - on how NOT to do it

Ill haft to connect to my Cerbo, update it, and see if the temp sensor configuration are there. It appear to be a new thing since 2021 or early 2022.

Keith

[Guest]

acoleman43 Could you provide a wiring diagram and the settings to operated a battery heater? IMO this would be worth filing in the reference area.

Again, an over the top system you have there.

Jim

[acoleman43]

acoleman43 Could you provide a wiring diagram and the settings to operated a battery heater? IMO this would be worth filing in the reference area.

Again, an over the top system you have there.

Jim

I will try. I hope I put this in the correct order of operation.


First the wiring part. I'm not good at diagrams so I'll provide pictures.

The back of the Cerbo has inputs for tank sensors, temp sensors and digital inputs on the left side and the 2 programmable relays and power input for the Cerbo on the right side.

First connect the Temp sensor(s). You can connect up to 4 temp sensors. Make sure you have the correct temp sensor for use with the Cerbo. The correct sensor part number is ASS000001000. This is the temp sensor for the Quattro, Multiplus and GX devices.

The temp sensor will have a red and black wire. Connect red wire on top and black on bottom by pushing the ferruled ends into the terminal block

For the relay, connect the positive wire (red) from the power source (probably battery) into the "COM" of the relay terminal block. Connect the positive wire (red) to the load (heating pad) to "NO" of the relay terminal block.

The negative wire (black) from the power source (battery) will go directly to the load (heating pad).

**NOTE: Make sure you fuse between the battery/power source and the Cerbo GX (Power In). This will help protect the Cerbo if you wire the relay incorrectly.






***One note: There is a limit to the power going through the relay. For most cases (12V) that limit is 6A. Make sure the load (heating pad) uses less than 6A.




To program the Cerbo, using a Touch GX, go to the Menu and find Settings. Open settings

Scroll down until you find "I/O" (input/output). Select I/O

Find Analog Inputs and select it.

Make sure the appropriate Temperature Input is on/activated





Go Back to settings and select "Relay"

Find the appropriate Relay (The relay the load is connected to on the relay terminal block), and select it. Select Temperature.

Go back to the Relay selection and select Temperature control rules

Select the appropriate Temperature Sensor to open the conditions settings.

In temperature control rules activate the relay, make sure you select the appropriate relay, then input the temperature (value) you want the load activated and the temperature (value) you want the load deactivated.

*Note, you can configure 2 conditions for the same relay if desired.






That should be it. Hopefully I didn't miss anything.

[Guest]

acoleman43 Nice job! I'm really impressed with what you've done with your install.


Jim

[Popga]

acoleman43 All I can say is WOW!!!!!!

I had not thought of building my own - probably not in my wheelhouse. I would end up with a real mess and let the magic smoke out of the wires.

My intent is to get SOK or Battle Born, Lion or other good brand based on current reviews (Will Prowse), and build a heated box for them. What I am trying to figure out is the components and box and how to set the heater up for manual control. I had not thought of using the Cerbo GX so I will need to look into that. Thanks for the tip.

Great set up BTW.

Keith

Keith,
I just replaced my Lion Energy batteries with Battleborn heated batteries. The Lions were fine, and very light, but I wanted the heated batteries. The Battle born heated batteries come with a manual switch. You can install them with, or without the switch. If you install without the switch, and have connected a 14 AWG wire from the + terminal to the heater, the heater will come on and go off between factory installed parameters. If you do not connect the + wire to the heater, the heater will not come on. If you mount the switch, you manually energize the heater to come on in the same parameters, but only when you want it to. I installed mine with the switch.
They cost a bit more, but while dry camping in the Tetons in the upper teens, I wished I had them.

Erik

[Yoda]

I will try. I hope I put this in the correct order of operation.


First the wiring part. I'm not good at diagrams so I'll provide pictures.

The back of the Cerbo has inputs for tank sensors, temp sensors and digital inputs on the left side and the 2 programmable relays and power input for the Cerbo on the right side.

First connect the Temp sensor(s). You can connect up to 4 temp sensors. Make sure you have the correct temp sensor for use with the Cerbo. The correct sensor part number is ASS000001000. This is the temp sensor for the Quattro, Multiplus and GX devices.

The temp sensor will have a red and black wire. Connect red wire on top and black on bottom by pushing the ferruled ends into the terminal block

For the relay, connect the positive wire (red) from the power source (probably battery) into the "COM" of the relay terminal block. Connect the positive wire (red) to the load (heating pad) to "NO" of the relay terminal block.

The negative wire (black) from the power source (battery) will go directly to the load (heating pad).

**NOTE: Make sure you fuse between the battery/power source and the Cerbo GX (Power In). This will help protect the Cerbo if you wire the relay incorrectly.






***One note: There is a limit to the power going through the relay. For most cases (12V) that limit is 6A. Make sure the load (heating pad) uses less than 6A.




To program the Cerbo, using a Touch GX, go to the Menu and find Settings. Open settings

Scroll down until you find "I/O" (input/output). Select I/O

Find Analog Inputs and select it.

Make sure the appropriate Temperature Input is on/activated





Go Back to settings and select "Relay"

Find the appropriate Relay (The relay the load is connected to on the relay terminal block), and select it. Select Temperature.

Go back to the Relay selection and select Temperature control rules

Select the appropriate Temperature Sensor to open the conditions settings.

In temperature control rules activate the relay, make sure you select the appropriate relay, then input the temperature (value) you want the load activated and the temperature (value) you want the load deactivated.

*Note, you can configure 2 conditions for the same relay if desired.






That should be it. Hopefully I didn't miss anything.

Absolutely Fantastic

This explains what I am currently seeing a lot. I am sure I will have questions later, but for now I have a starting point. I owe you big time.
Keith

[Yoda]

I actually forgot I had this thread going

OK I thought I would update this.

Thanks to Howard and is foam desk build, and as I have a bunch of scraps I am conceptually looking at building a heated battery area in the front bay. I am looking at Li Time batterys as SOK is having a rash of BMS issues, Most of the Li Time don't have low temp cutoff or heaters, thus the cheap price. Howard's howson link to the Nomad's information building with foam is Great. Thanks Howard. https://www.youtube.com/@falkornomad...oam%20building It answered a bunch of build question for me.

Now for heating pads. RecPro has a bunch https://www.recpro.com/search.php?se...ection=product. However many are close to the 6A the Cerbo limit is. They also have built in sensors - not sure if that would cause a problem. Are there other heating pads I should consider that draw under 6A? Amazon has a bunch - just don't know what good. I was thinking I would need two pads. . I plan to put the pads under the batterys on top of the insulated foam bottom. I assume I can use a relay if pads draw more than 6A acoleman43 Can the cerbogx relay trigger a second relay?. That may sound like a dumb question - sorry

Foam box - Fire hazard? If I put a foam top above the batterys withe wiring running out through the foam are there any precautions I need to take? Otherwise I can build a plywood box and use fire resistant insulation - not as good an R value as foam. Probably safe. Or is foam on the sides and the fire resistant insulation good for the top?

Last I think I need to update the firmware on my CerboGX. to see the temp sensors and switches, but I could be doing something wrong on my tough 50 or the blue tooth connection using Victron connect.. Can that be done blue tooth, or do I need to hard wire connect to my laptop using the MK3? Maybe I should tag Neil ncitro

Again in the concept stages here and it would be spring before I even consider doing this. In time I know my 6V will fail and lithium is now down low enough to really consider replacing them. Maybe next fall. Now I need to go back and re read the cerbogx manual - good thing I posted the link - I am having too many Yoda Moments remembering things.

Keith

[ncitro]

Yoda I have not played with the temperature monitoring a ton, but I believe the ones you want would be wired (as opposed to the Ruuvi wireless temperature sensors). There is a sensor for the BMV that goes on the battery itself and reports the actual battery temperature. You need to toggle those settings in the BMV to tell it that it is a temperature and not a second battery voltage. Once that info is in the system then you should be able to program the relays in the cerbo to run the heaters. You can do that either directly, or use them to run a bigger relay to run the heaters like what we did for the DC to DC. In those the smaller relays in the upfitter switches run the big solenoid that runs the DC to DC.

BMV Temperature Sensor (not sure what you do if you have a SmartShunt rather than a BMV):

https://www.victronenergy.com/meters...or-for-bmv-702

You might also be able to use a temperature sensor into your MultiPlus:

https://www.victronenergy.com/live/temperature_sensors

[Jlawles2]

https://www.litime.com/products/liti...aee9b4f7&_ss=c low temp heating

https://www.litime.com/products/liti...aee9b4f7&_ss=c low temp charging cut off


NOTE: they also have them in 100ah version.

[acoleman43]

Yoda

acoleman43 Can the cerbogx relay trigger a second relay?. That may sound like a dumb question - sorry

You can use the Cerbo relays to start a generator. So I would say the answer is yes. If you use the relays to turn something on/off based on temp, I would think you have the cerbo relay trigger a larger relay (kinda like you would do with upfitter switched in your truck if you have something that takes more than 40 amps).