Tuesday, July 29, 2008

More on charging

I've been busy and have not blogged my progress lately. I'm trying to get a second working battery (which the TWIKE firmware requires for operation) to be recognized. At this point, I have tried two different BMS boards in three batteries to no avail. I'm afraid the BMS is bad in both batteries. Not surprising given the amount of stuff I found growing on them (mold, etc). I'm stuck with either pulling the BMS boards and doing a component level debug or trying to swap for some other unknown batteries. Not sure what I will do. I did get my order from digikey which gives me a set of connectors for all the 3 connector types used by the batteries. With those, I made a set of extension cables so now I can debug the batteries outside the card. Very handy and much safer I might add. If anyone wants the digikey part numbers for the connectors drop me an email (I'm also in the process of setting up a english based wiki for the twike where I can post such technical details for other to find and to share). More on that when I finish getting it setup. I now also have the means to spy on the RS485 bus to decode the BMS protcol. This is all in advance of attempting to build my own Lithium based battery pack (will have to emulate BMS responses to make car firmware happy). I have the battery service program which will give me a let up on decoding the protocol. The program is all in German but I'm part way through in translating all the screens to english. I'll post that on the Wiki when I'm done. So enough for tonight.

P.S. I'm on vacation for the next 3 weeks so I probably won't have any updates for a while.

1 comment:

M@ said...

Hi Phil!

Let me know if I can be of any assistance -- I take care of Twike 433, and while I am not a competant electrician, I can hopefully put you in contact with folks that are (I pointed out your blog to Walt Breitinger, so hopefully you should hear from him soon -- he's drivin a Twike in the US for 11 years, 80,000km). Drop me a line at childrss@illinois.edu