All my logs show Voltage spikes during braking and some brake current. This is a good read why the voltage increase during braking by MGM Compro.
http://mgm-compro.com/pdf/en-motor-braking-050409-g.pdf
6 KiloWatt A123 Racer
GTP-Pletty Big Maxximum+RX8. GTP-C50-6L Hacker+RX8. CRT.5-Pro4+ZTW esc.
24s2p EVG SX 49.6mph Ebike.
18s4p Raptor 60mph Ebike. 11.5KW