Boxer EV v4 Photos

| | Comments (3)

I thought I would post some images of the latest iteration of my Piaggio Boxer EV project. I hadn't actually shown the Prius batteries mounted, even though I had done that almost a year and a half ago.

This is the front, showing new 9 watt LED front bulb. Blindingly bright:

PiaggioBoxerEV4 001

This is the Prius pack mounted in the 6s2p configuration, given me 43.2 volts @ 13 Ah nominal. I made the battery carrier myself. The motor speed controller is below the pack, but it's hard to see from this angle:

PiaggioBoxerEV4 002

This shows the new style HobbyKing motor mounted. The new motor was longer than the old one (even though the specs on HobbyKing's site weren't updated) which meant it could no longer fit in the old motor mount. I had to weld together my own motor mount. Right now, I'm holding the motor only on one side, leaving the other open for the cooling fan (made from a PC computer fan) - note that the motor spins counter-clockwise from this perspective, so the fan draws air into the motor. I think I'll eventually end up making a retention bracket for the right side as well, to prevent too much stress on the bearings on motor:

PiaggioBoxerEV4 003

This left hand side shows how the motor was moved forward in order to fit:

PiaggioBoxerEV4 004

A little view of the wonderful CycleAnalyst:

PiaggioBoxerEV4 005

This is the new reverse-current board that I made using MOSFETs. It's not perfect, but it's more efficient than the blocking diodes that I used -- which were expelling 1.7 volts @ 100 amps == 170 watts when the motor was at full speed!

PiaggioBoxerEV4 006

Ending with another side view.


Please feel free to post comments and questions! You can sign in using Facebook, Google, OpenID, Mixi, Yahoo, and a variety of other authentication systems.


Someone on the endless-sphere forum asked me about battery usage / efficiency. Here was my response:

The peak amps are during the acceleration phase. This thing accelerates really fast! I keep meaning to get one of the iPhone apps that can tell you how many Gs your vehicle can pull.

Once it gets up to cruising speed, the amps drop down drastically (I can't easily see the CycleAnalyst while I'm riding, but I'm guessing 40-50 amps). Actually, I guess I could back-calculate using the watt hours.......

45 Wh / km @ 40 km / h = (the km and the h cancel out) .... 1800 watts

1800 watts @ 43.2 volts = 42 amps


Nice set up you got there!
I found your blog through Google while i was looking for ways to charge my Prius NiMH pack effortless just like i always charge my SLA's.

I bought the prius pack last week from some company which salvaged a front wrecked 2010 Gen.3 Toyota Prius. The batteries seemed in excellent order and all of the 28 modules were showing 7.5/7.6V when i took them out of their assembly. They will soon be used in my Novox C20 electric scooter at 8s2p configuration.

Unfortunatly i cannot find any info over the method how you charge your 6s pack. Could you please share this information? :)

Thanks in advance!


from The Netherlands

Dear Tim -

Thanks for the question! I'll respond with a new article in the blog.


Leave a comment

About this Entry

This page contains a single entry by Karen Nakamura published on June 5, 2011 2:51 PM.

Sailing faster than the wind - with a propeller! was the previous entry in this blog.

Philips LED light bulb revealed - remote phosphor 12.5 watt is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.