Comments on: Ford Announces BEV Focus for 2011 http://www.sequence-omega.net/2009/05/06/ford-announces-bev-focus-for-2011/ Fundamentally Different Sun, 18 Dec 2011 06:36:58 +0000 hourly 1 http://wordpress.org/?v=3.3 By: Anthony http://www.sequence-omega.net/2009/05/06/ford-announces-bev-focus-for-2011/comment-page-1/#comment-59 Anthony Sun, 10 May 2009 21:14:01 +0000 http://www.sequence-omega.net/?p=357#comment-59 The problem with the Altairnano or any battery for PHEVs and EVs is that at a low number of cells/pack, you have to make sure that at 80-90% discharged you can still get the necessary power out of the pack to drive and pass on the highway. If the battery puts out 1400W/kg at 50% DOD but only 800W/kg at 90%, you better make sure that there are enough cells to source 120-150kW. This will be less of a problem in the future, as cell energy densities and power/weight ratios go up. The 2020-spec battery of 200Wh/kg and 2500W/kg could source 150kW from a 12kWh pack. The <a href="http://www.sequence-omega.net/2009/05/08/enerdel-lithium-titanate-batteries/" rel="nofollow">EnerDel article</a> I wrote talks about this some more, as their spec sheets have their cell discharge/power graphs. The 200Wh/mi might be a bit low - maybe 250 is more appropriate. Then again it all depends on city/highway driving and driving style. 250Wh at 100 miles at 60% DOD is 42kW. The problem with the Altairnano or any battery for PHEVs and EVs is that at a low number of cells/pack, you have to make sure that at 80-90% discharged you can still get the necessary power out of the pack to drive and pass on the highway. If the battery puts out 1400W/kg at 50% DOD but only 800W/kg at 90%, you better make sure that there are enough cells to source 120-150kW. This will be less of a problem in the future, as cell energy densities and power/weight ratios go up. The 2020-spec battery of 200Wh/kg and 2500W/kg could source 150kW from a 12kWh pack. The EnerDel article I wrote talks about this some more, as their spec sheets have their cell discharge/power graphs.

The 200Wh/mi might be a bit low – maybe 250 is more appropriate. Then again it all depends on city/highway driving and driving style. 250Wh at 100 miles at 60% DOD is 42kW.

]]> By: Jeff Sutter http://www.sequence-omega.net/2009/05/06/ford-announces-bev-focus-for-2011/comment-page-1/#comment-58 Jeff Sutter Sun, 10 May 2009 14:16:40 +0000 http://www.sequence-omega.net/?p=357#comment-58 It's interesting that Altairnano batteries are rated to get 5000 full 10C charge/discharge cycles @ 100% DOD. Five times the cycle life of the high impedence 2nd Gen Lithium batteries considered for the Volt. I wonder how the .2kwh/mile metric could be achieved - the Phoenix SUV demo's use .33kwh/mile and it looks like the Aptera will use 1/2 that (.17kwh/mile). What's the Focus going to look like? It’s interesting that Altairnano batteries are rated to get 5000 full 10C charge/discharge cycles @ 100% DOD. Five times the cycle life of the high impedence 2nd Gen Lithium batteries considered for the Volt.

I wonder how the .2kwh/mile metric could be achieved – the Phoenix SUV demo’s use .33kwh/mile and it looks like the Aptera will use 1/2 that (.17kwh/mile). What’s the Focus going to look like?

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