How worn out is the "good" ForkenSwift battery pack (currently in the car)?
Some simple calculations to get an estimate:
- It's a 10.56 kWh nominal pack (8 batteries * 6V * 220 Amp hours rated per battery) (V * Ah = kWh).
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- 80% of the new pack capacity is 8.45 kWh (10.56 * .8).
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- Looking @ an average of 5 similar drive cycles on the existing pack to an estimated 80% depth of discharge (W.A.G. - impossible to say without a hydrometer), it could travel 28.1 km, in warm weather (>20 C / 68F).
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- The average energy from the wall to recharge was 4.36 kWh.
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- Assuming 85% charging efficiency (another W.A.G.), then the capacity to 80% DOD of the current pack is 3.7 kWh (4.36 * .85).
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- The car's efficiency based on these figures is 132 Wh/km (3.7 kWh/28.1km), or 212.4 Wh/mile, or 158 mpg(US) equivalent energy consumption.
So, the current pack has
43.8% of the capacity compared to "new", to 80% DOD (3.7 kWh / 8.45 kWh).
So what would the car's range be on a new set of batteries?
64 km (8.45 kWh / 132 Wh/km) or about
39.8 miles. In warm weather.