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This is the first version of the Pathfinder BMS datasheet. (The file will update when we revise the datasheet, so link to the file URL if you want to share it, and your link will stay up to date)
Datasheet: Pathfinder BMS
8 thoughts on “Datasheet: Pathfinder BMS”
Leave a Reply to overkillsolar Cancel reply
RoHS statement for the win.
Looks killer! Just ordered 4.
I think I know the answer to one question, but I hope you can confirm: all the BMS are the same. When we select 8-cell or 16-cell etc…, it’s just a different terminal board included, correct?
I have some 24-volt systems and some 48-volt systems. I’m wondering if I should just get the 16s. I could still use that board for an 8s configuration, if I wire it correctly?
Or can you sell or link us to the terminal screw boards that are included with the BMS?
ahh nvm I found the answer in the data sheet.
I will put extra terminal boards up for sale at some point
The manual states it will handle up to 12 cells lithium-ion/NMC. I was under the impression max voltage on most NMC cells is 4.2V, so 12 cells would still be well below 64V maximum. This BMS cannot handle 14s NMC packs?
Correct, 14 cells of NMC would be ok.
Out of curiosity is this being written in MicroPython or Arduino’s “version” of the C language? Will you be making the U2F files open sourced pre-compiled for tuning by hobbyists? So we can compile our own U2F (at our own risk of course!!).
Really looking for these to come out, I’m super heavy into micro controllers and will be curious how its works. I see you have the little OLED screen we are all used to (we = microcontroller crowd) I’m going to go out on a limb and guess you are using an ESP32 for WiFi and BT ?
Oh haha just looked at the PDF and gives most of my answers lol. Nice job going with MQTT, I hope you include lots of data points. I can build a beautiful Grafana page to display all the data real time. One thing that I think is a bit odd, is that you have the screen and buttons on the BMS and not too far away are the main battery connections. Not exactly an area you should be fumbling around with your hands. Its interesting how you have designed this BMS to be more of an “Up front in your face” device instead of just buried in the case like most. Granted you can do that too it seems with yours.
I wish I could have been part of the Engineering team. I have micro controllers all over my house monitoring anything you imagine. It goes without saying that the Texas Instruments chip’s you are using are proving to be accurate which is awesome. I think I had looked at some to use simply as extra monitors but I mean lets face it, today’s modern high quality Solar Charge controllers give me all the data in the world available from the web or not.
This is a DIYer’s BMS like you said, and I think its super cool! I can’t wait to see the iterations you go through with it. Those people adopting version 1.0 code I salute you! You will be finding the bugs for the rest of us! That’s no disrespect all programs have bugs! I’m curious to see how well the thermals turn out to be too. I’m sure you guys will be pushing these to the absolute limit for days and days to ensure stability and that no chip decides to lose its marbles after extended high temps. I couldn’t tell but does the ESP32 have the external antenna attachment too or no? ESP32 transmission stability suuuuucks at least with my router and setup. So much so that I’ve built into my code to reboot some devices to ensure WiFi connectivity. Are you using native EspressIF programming on the ESP32 (C basically) or Arduino “C” or micropython/circuitpython? I wish I come by your shop and hang out. I’m in Jacksonville. I also wish you guys sold higher AH batteries but I understand that’s not your gig. I’ve heard great things about your batteries and actually would love to build like a 16S3P setup, but man too expensive compared to the competition!
Hoping your GitHub page will be a welcome and open place. I mean surely you are borrowing at least the algorithm workflows from JBD, not saying you are copying code, but I’m sure their code gave you ideas 🙂
Well wishes and I think I’m on the notify list not sure if it worked, if not please add me! I wanna get my hands on one and throw it on all the analyzers, scopes and de-compilers to see the goodies! Might inspire me to build one for fun one day!
Love your company. You guys should post some videos. That would be awesome!
We are programming in plain C with ESP-IDF.
The ESP32-S3 is a WROOM module with the built in antenna.
We will not be making the firmware open source because it would make it way too easy to clone the entire BMS.
We will be taking suggestions and putting out updates.