Mon Jul 09, 2012 11:55 am

I've been thinking about the approach leec presented (above), whereby you drive 50 miles in 50 minutes and then spend 30 minutes Quick Charging, yielding (24hrs*50miles*60min/hr)/(50+30) = 900miles as the theoretical maximum iMiEV daily mileage using Quick Charging (CHAdeMO).

Now, using this same approach, here's the analysis for Level 2 and Level 1 charging...

To start with, even though my own latest summary shows that my overall average **wall-to wheels** consumption is 4.2 miles/kWhr, because of the relatively high speed in this example I will use the very conservative EPA average rating of 3.333 miles/kWhr for this discussion.

My measured wimpy Mitsubishi EVSE charging power is 0.9kW at exactly 120vac and using my SPX EVSE gives a measured 3.06kW at exactly 240vac. This number is actually quite constant until the last hour where the BMS does its cell balancing routine and the power diminishes until cutoff. Ignoring the 10-minute timeout the BMS seems to randomly take (I suspect to recalibrate itself), and ignoring the last hour taper charge, for the sake of this discussion let's say that the Level 1 (120vac) charging is 0.9kW and Level 2 (240vac) charging is 3.0kW, from the "wall".

**Level 2**

A charging rate of 3.0kW * 3.333miles/kWhr results in 10miles/rechargehour. To recharge the car after having driven 50 miles we get 50/10= 5 hours. Thus, we can say that we get back to the charge level we started with in five hours and fifty minutes, or 5.833hr, after starting off on our 50-mile trip. Ok, so for 24 hours that gives us 24 * 50/5.8333 = **205.7miles** theoretical daily maximum using 240vac (level 2) recharging.

**Level 1 (8A)**

A charging rate of 0.9kW * 3.333miles/kWhr results in 3.0miles/rechargehour. To recharge the car after having driven 50 miles we get 50/3= 16.67hours. Thus, we can say that we get back to the charge we started with in 16.67+(50/60)= 17.5hours after starting off on our 50-mile trip (ugh!). Ok, so for 24 hours that gives us 24 * 50/17.5 = **68.6miles** theoretical daily maximum using the Mitsubishi 120vac (level 1) EVSE.

**Level 1 (12A)**

We've shown that the iMiEV accepts a 12A 120vac input from non-Mitsubishi EVSEs, which, (scaling .9kWmeas/.96kWlabel) would yield 1.35kW possible at 120vac. 1.35kw * 3.33miles/kWhr results in 4.5miles/rechargehour. To recharge the car after having driven 50 miles we get 50/4.5= 11.11hours. Thus, we can say that we get back to the charge we started with in 11.11+.83hours= 11.94hours after starting off on our 50-mile trip. Ok, so for 24 hours that gives us 24 * 50/11.94 = **100.5miles** theoretical daily maximum using a 12A 120vac (level 1) EVSE.

**SUMMARY**

As our first shot using a speed of 60 miles/hour and assuming the conservative EPA figure of 3.33miles/kWhr applies to this speed, rounding off slightly we can say that in ONE DAY the iMiEV can theoretically travel a maximum of -

**900** miles using CHAdeMO Quick Charging

**200** miles using Level 2 (240vac) charging

**100** miles using a more robust Level 1 (120vac 12A) EVSE

**70** miles using Mitsubishi's Level 1 (120vac 8A) EVSE

Once I get more data showing what the exact power draw is at various speeds, we can make up a table which can more accurately reflect the real world, and especially see what impact reduced speeds would have on these daily range numbers.

How close to these theoretical maximums can you get?

**EVs:** **2** Wht/Blu SE Prem., '13 Tesla MS85, **3** 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)

**EV Conv:** 156v '86 Ram PU, 144v '65 Saab 96

**Hybrids:** 48v1kW bike

**ICE:** '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV