WiSnap + Elithion BMS
The Elithion Lithiumate BMS uses a serial cable to talk to the computer. That’s kind of a pain to see additional information that the SOC display doesn’t tell me. It is also nice to see how the batteries are doing “on the fly”, or when I’m charging at work.
I bought a WiSnap and made a little case for it:
The red/black cord is for a 9v power supply, but it doesn’t need it as it can get its power from the RS-232 input. I can now connect to an adhoc Wifi network with my iPhone (dubbed “PlugBugBMS”) and see all the serial data from the BMS controller. Pretty cool!
I still want a better display, and eventually I want some easy software that displays cool battery status in a nice graphical package. I thought the serial port might be good to do it, but it won’t work. I need to tap the CAN bus line and somehow emit the data to my phone. Bluetooth would work, but the bluetooth connection kit (and SDK) for the iPhone is not free. I’m also not sure if the iPhone can connect to more than one bluetooth device, and I really want it to always connect to my hands free headset and car stereo. Now…only if that bluetooth device could tap into the CAN bus and report additional packets of information to a custom app on the iPhone…
DevToaster (one of the people from our group now works there) has an app that uses a CAN adaptor that broadcasts over wifi. Gives all sorts of info.
This sounds like a job for a cheap iPod Touch or does it not have bluetooth?
Not sure if this would help, but I put together a proof-of-concept iOS app that uses a Southern Stars SkyWire cable to graphically display output data for (in this case) a CycleAnalyst amp-hour meter. (See my aforelinked GitHub account).
While you don’t need to jailbreak your device, you will need to be able to compile and sign the code, write your own parser for the serial data stream, and figure out a display that makes sense. Sounds like a fun project :)
Of course that doesn’t help you with talking to a CAN bus. http://gopointtech.com/ has a device that presumably does this, since some vehicles use CAN for their OBD II link. But it might be limited in some way to only J1939 communications, which may or may not be what your BMS is emitting.
They’re supposedly working on a bluetooth version. I’m not sure whether their business model depends on making life difficult for unauthorized third-party developers.