REAP Systems in England did test that in a lab last year. You can see a video presentation they did on the EVTV web site. Go to video archives, August 16, 2013. A direct link is http://media3.ev-tv.me/news081613-iPhone.m4v. The presentation starts at 23 minutes and the results are around 36 minutes.
Instead of sanding they used a steel bristle brush to remove the tarnish from the terminals and busbars. They discharged the cells at 300 amps in 60 second bursts 30 times. The BMS was monitoring individual cell temperatures and if they exceeded 45C it would reduce the current. They strapped 7 100Ah cells together. With uncleaned terminals they got one cycle before having to reduce the current because of temperature. The warmest cell got up to 55C after 10 cycles. With cleaned terminals there was no reduction in current until after 11 cycles when the warmest cell got up to 45C. The warmest cell eventually got just above 50C but after those 11 cycles they'd already drawn half the capacity of the cells. Interestingly there was virtually no difference when they added the grease. So if you think the grease will help prevent corrosion that's fine. But it doesn't seem to do anything to help the connection. --Rick On 7/31/2014 12:43 PM, Michael Ross via EV wrote:
With aluminum, you just cannot expose bare un-oxidixed metal, it is not possible to do this, so I am not happy with the sanding idea. The sanding has to be helpful on some other basis if it is indeed helpful. Be interesting if someone has compared greased un-sanded to greased and sanded.
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