Electric Bikes - Alternative Mounting of Bionx Battery

The triangle of this bike is 2 inches too narrow to accept the BionX battery. So I was thinking of mounting it upsidedown, direcly under the tube it would normally be mounted on. The tallest part of the battery would end up near the bottom of the triangle, between the pedals. Any thoughts? This is, essentially, the same bike:
http://www.kcn.ne.jp/~vp-gyro/newbike/amp/b4_01.jpg

What are you going to attach the mounting bracket to? The bracket is not the sturdiest of things when attached to the bottle cage mounts. Mounting is upside down will put a lot of wieght on a presumably weakly mounted bracket.

I would look into mounting it from a rear pannier rack, you just need to find one that will work with your rear suspension.

Yes, the mounting brackets were going to be a problem. And since I posted this I realized that all the dirt, gravel, and wetness is going to be sprayed at the battery in that position. I did find a nice seatpost beam mount that I could use but I was trying to keep an already light bike.... light. But, I guess, with the assist... it's not an issue. Thanks for your reply.

Could you mount it on top of the top tube?

Yes, I thought of that. And I looked for mounting brackets on the net that wouldn't look out of place. No luck so far.