Saturday, March 31, 2012

Fill 'er up!

I decided to use the gas tank to mount some of the electronics, and to keep the existing front mount point for the seat intact. The first step was to remove the fuel pump/filter and the float, then completely empty the gas residue in the tank. I then put a few cups of water and a little liquid soap in there and sloshed it around to make sure no gas was left behind... then to make really sure I put a heat gun on low and ran it into the tank for about 15 minutes to completely dry the tank. A Sawzall then made quick work of cutting the bottom half of the tank off.

I then took a grinder and cut the filler connector off and ground it flat to the top of the tank. This will let me mount the J1772 connector where the fuel inlet used to be. I needed the 1/2 inch of room so that the J1772 would drop low enough for the fuel door to be able to close.

It is mocking me...

I wasn't sure if I could get 36 of the 100Ah cells in the frame and still be able to get the skin back on the bike (My goal is for the bike to look as stock as possible.) As seen earlier, one of the NTEAA members made some wood mockups for the 60Ah(b) Sinopoly cells for me, but I needed to see if the 100Ah cells would fit. With the help of a couple of the Dallas Makerspace members, I built 40 of the 100Ah and 36 of the 60Ah size mockups out of construction paper. We used Pepakura software to model the cells and used a laser cutter to cut them out, then folded and hot glued the 60's... on the 100's I used clear tape, I was tired and gluing took too long.

I laid out the 100Ah cells and it quickly became obvious that I wouldn't be able to get them to fit, even if I used all of the space up front in the frame and both of the pannier cases at the back of the bike (leaving me no storage at all.) I then laid out the 60Ah mockups and discovered that I would have plenty of room with them.

36 of the 60Ah cells will give me a 115.2 vdc, 6.91kWh pack, which should yield at least a 45 mile range with 80% DOD, assuming 120 wh/mi. A 36 cell pack will use just under 38 liters of volume, and weigh just over 68 kilos (150 lbs). I'm estimating that the cost for the pack will be under $3000, plus shipping.

The 40 100Ah mockups have been donated to the NTEAA for members to use for making their own battery boxes, etc.


Travis at got me an excellent deal on a Curtis 1311-4401 programmer for my 1231 controller. This will let me tweak the controller.

Friday, March 30, 2012

Technical Difficulties...

I'm sorry for the delay in updating this blog. My laptop croaked and all I had to access the net while it was being repaired was my phone. I'll be doing several updates over the next day or two.