LEAF’s Battery Pack

Key Figures:

• 48 modules (in series)• 660 lbs total weight• 360 V nominal voltage • 24 kWh rated capacity (66 Ah)• 21 kWh available capacity• 192 laminated prismatic cells

AESC Module - Key Figures:

• 8.3 lbs per module• 4 cells per module (2 in series, 2 in parallel)• 7.5 V nominal voltage• 0.5 kWh rated capacity (66 Ah)• $662 retail price

AESC Cell - Key Facts:

• 1.8 lbs per cell• 3.8 V nominal voltage• 125 Wh rated capacity (33 Ah)• 2 x better cooling than traditional cylindrical cells• LiMn2O4 with LiNiO2 cathode (Nippon Denko)• Graphite anode (Hitachi Chemicals)• LiPF6 EC type electrolyte (Tomiyama)• Celgard PP dry separator

Battery Model # 1:

• 3 modules per battery gauge bar (1.5 kWh)• 16 bars total • 12 bars visible• 2 bars reserve• 2 bars silent (1x top, 1x bottom)• kWh remaining: (visible bars + 2) x 1.5 kWh

Battery Model # 2:

• 75 Wh per SOC tick• 320 total SOC ticks• 281 available SOC ticks• kWh remaining: SOC ticks x 75 Wh / 1000

Range Estimate:

• Range: kWh remaining x miles/kWh (Energy Economy)• Environmental factors (temps, tire pressure, driver, wind)• Reset energy economy gauge before the trip or trip segment

Accuracy & Predictability:

• Flat discharge characteristic • Linear SOC tick characteristic• 95% model accuracy

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Fun Stats:

• 4.10V cell voltage when full• 4.04V cell voltage at 80%• 17% (4 kWh) reserve capacity

• 3.92V est. cell voltage at 50%• 0.40V est. voltage drop from 12 to 1 bars• 30mV est. voltage drop per visible bar

• 85% charging efficiency at 240V (3 kWh / 60 mins)• 75% charging efficiency at 120V (1 kWh / 60 mins)

Sources:

• AESC (Nissan and NEC)• MNL forum• Volt forum• Data samples from LEAF owners

Links:

1. http://www.eco-aesc-lb.com/en/product.html 2. http://gm-volt.com/forum/showthread.php?5243-Volt-thermal-

management-system-temperature-band&p=43562#post435623. http://www.mynissanleaf.com/viewtopic.php?f=31&t=42954. http://www.mynissanleaf.com/viewtopic.php?f=44&t=47605. http://green.autoblog.com/2011/08/03/need-to-replace-a-

nissan-leaf-battery-hows-19-392-31-753-u/6. http://www.youtube.com/watch?v=FiyRxxbkHH07. http://www.mynissanleaf.com/viewtopic.php?f=9&t=22658. http://www.no-url.com/LEAF/LevelIIICharging_01-30-11.html