I bought a Di2 upgrade kit, which had an internal battery, which I intend to install on a new Di2 ready frame. In the meantime, my current bike does not have internal routing options and I was wanting to use the upgrade kit on my current bike until I get the new one.

I thought I had two options for mounting the internal battery. 1. zip tie it to the downtube bottle cage, 2. zip tie it to the below NDS chainstay.

With either mounting I would use tape to make the wire connection a little more waterproof.

Any reason why I should not do this? Can you think of other options, preferable ones that do not require the purchase of a new battery, charger, battery mount harness.