Power Cord for Battery Operation ie, JRDG BS-8

If I use the battery for the power amp (ie, the JRDG battery BS-8 for the Model 8Ti), would the power cord affects the sound quality?
I certainly don't think so, but I never tried anything other than the stock cords when I had my battery powered Rowland Model Sixes. However, I did notice a big improvement when I switched out the stock Cardas umbilical cords on my Rowland Model Twelves and Synergy with FIM Gold custom-made umbilical cords.
When drawing off battery supply the AC cord shouldn't be an issue (it's out of circuit isn't it?). However as PC says, the DC umbillical cords are definitely in circuit & would affect sonic signature.
I do agree with Bob and PC that there is a marked improvement when you switch the Cardas umbilical cord/s with the FIM Gold ones.