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Discussion Starter #1 (Edited)
I've started this thread to hold information on using the OBDIIC&C based LTO CAN device for non car uses.

The device can be used to listen to the isolated LTO CAN BMS data and then control or interact with external devices..
Attached is a minimal OBDIIC&C 18F2680 build schematic with information on OBDIIC&C pin availability & capabilities.
It uses the standard OBDIIC&C pcb you are familiar with. Components not shown on this schematic can be omitted from the pcb.
You also require the CAN daughterboard fitted (not shown) as per my previous LTO CAN videos.

Points to note..

1) If controlling relays, always add back emf diodes across the relay coils.

2) A lot of the repurposed inputs and outputs into the PIC processor on the PCB are not protected by current limiting resistors etc as it was not part of the original design.
Use suitable limiting resistors in your own add ons to compensate for this.

You must ensure you do not exceed the 18F2680 specifications.
Most pins are limited to 5V Logic level and 20ma maximum output.
Each PIC port A,B,C also has a maximum combined pin current capability.

3) The two open collector NPN 2N3904 transistor outputs have a 30V 200ma capability.

4) The serial data 3.5mm audio jack output port is designed to use the special Picaxe AXE027 usb cable.

5) You can log serial data directly into EXCEL using the above cable and the old PLX-DAQ software.
This logging is widely discussed in my previous posts on the forum.

6) The software for the device is based on all the LTO & OBDIIC&C work I have done so far over the years.
Specific features may be added as people request them.
The source code will be available by special request.

7) The firmware is not ready yet! I will work on that as time and a million other projects permit.

8) I will add a descriptive video detailing the OBDIIC&C PCB later.


Premium Member
2,891 Posts
Thanks Peter.
I intend to do just as his thread describes.

Re-purposing allot/most of my batteries I've accumulated into an expanded stationary battery system at my house.

I'm aiming to use this LTO CAN BMS interface as part of a combined total ~12kwh battery system.

I'll be re-wiring Fit Toshiba SCiB LTO sub-packs into 12p12s .. a ~6.6kwh ~24V battery.

After the 3p48s A123 pack is done for my car .. that should leave enough A123 pouch cells to also make up to 13p8s .. a ~6kwh ~24v battery.
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Premium Member
2,891 Posts
So for the LTO you only need one BMS board? 12 cells.
That rewiring to 12p12s is the hope / intention.
That would allow for :

1> Possibly easy future house expansion .. 24s for 48v battery , etc .. in theory the CAN would let different IDed 12s BMS boards just add on.

2> Possible future car experiment with 4 of the 12s LTO BMS boards , and the 3p48s LiFePO4 in car battery.

3> Possible future home experiment with the 12s LTO BMS boards , and the house ~6kwh LiFePO4 battery.

4> Would leave 'extra' 12s BMS boards .. which could help others who might need to swap a few BMS board so they get their unique IDs.


If the rewiring fails for some reason .. I could always fall back on 12s12p.
But .. that would use all 12 BMS boards just for the house pack alone .. possibly need 12 unique IDs .. and none left over for any of the other possible experiments.
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