by donald (Posted Fri, 13 Sep 2013 06:23:11 GMT)
hmm... interesting.
I can't say that is quite my experience with the Renault battery. Keeping to/below ~15kW seems to be fairly optimal.
I would say you should look suspiciously at anyone saying drawing/charging above 1C is no less efficient than below. I guess if you aim for 1C at 22kW, then inevitably in practice you will be occasionally drawing 10kW and sometimes 30kW. Over that 1C hurts the range/capacity. I guess when I aim for 15kW I still get good mileage because my occasional 'power excursions' stay generally below the 25kW mark. These quoted tests probably benefit from being able to pull a steady 22kW, on some flat test track, without excursions above 1C
drees wrote:
Actual testing data says that round trip efficiency goes up at higher speeds:
http://avt.inel.gov/pdf/fsev/fact2011nissanleaf.pdf
http://avt.inel.gov/pdf/fsev/fact2011nissanleaf.pdf
hmm... interesting.
I can't say that is quite my experience with the Renault battery. Keeping to/below ~15kW seems to be fairly optimal.
I would say you should look suspiciously at anyone saying drawing/charging above 1C is no less efficient than below. I guess if you aim for 1C at 22kW, then inevitably in practice you will be occasionally drawing 10kW and sometimes 30kW. Over that 1C hurts the range/capacity. I guess when I aim for 15kW I still get good mileage because my occasional 'power excursions' stay generally below the 25kW mark. These quoted tests probably benefit from being able to pull a steady 22kW, on some flat test track, without excursions above 1C
