One of the most recognizable electric vehicles on the road, the Nissan Leaf, has a battery capacity of 24 kWh. The battery in the Nissan Leaf is manufactured and assembled by the Automotive Energy Supply Corporation (AESC), a joint venture corporation between Nissan and NEC located just outside of Yokohama, Japan. Until Tesla’s Gigafactory comes on line, AESC’s factory remains the largest automotive battery manufacturer shipping nearly 90,000 batteries annually, mostly into the Nissan and Renault EVs and hybrids. AESC discloses on its website some pertinent details about the battery and its characteristics. The weight of the Nissan Leaf pack checks in at 648-lb, about ½ that of the Tesla’s pack, yet only ⅓ its capacity. I will revisit this point below. The first photograph shows the pack with its top protective metal case removed. The pack measures approximately 1570.5 x 1188 x 264.9 mm (61.8 x 46.8 x 10.4 in). Photograph of the battery pack for a Nissan Leaf electric vehicle. One can readily see some of the smaller modules that make up the pack. The first observation we make is that the pack consists of smaller modules.
In fact, AESC tells us that there are 48 of them, each measuring about 303 x 223 x 55 mm (11.93 x 8.78 x 1.38 in) and weighing about 3.8 kg (8.4 lb). Each module is made of four individual pouch (also known as laminate) cells, each cell like the one shown in the next photograph. The four cells are electrically configured as 2 in series and 2 in parallel. This prior post teaches more about series and parallel configurations. Photograph of the battery pouch cell used in the Nissan Leaf pack. AESC shares some of the electrical characteristics of the cell. Each cell is rated at 32.5 Ah, or about 10X that of the 18650 cell used in the Tesla. It uses a different material for the cathode called lithium-manganese-oxide with nickel oxide (LiMn2O4 with LiNiO2) that is inherently safer than the lithium-cobalt-oxide cathode material used in mobile devices and the Tesla pack.
The cell’s voltage chart shows a maximum cell voltage of 4.2V. Rated nominally at 3.75V, one pouch cell can store a maximum 122 Wh of energy, or about 10 times what an iPhone 6 Plus battery can store. So let’s do some math. Each module contains 4 cells, so that’s a total energy of 488 Wh. This is now a substantial amount and hence one should exert plenty of caution in handling or using such modules. The voltage chart above shows that one cell can deliver at least 90A of current. This estimate is not far off from the Leaf’s vehicle rating of 90 kW (120 hp). In any case, one can see that both current and voltage values are high, warranting special design measures to ensure safety. But for the added safety of the LMnO material, Nissan incurs some important penalties. First, the intrinsic energy density of the individual pouch is only about 320 Wh/L. Compare this to nearly 700 Wh/L for the Panasonic cells used by Tesla. Why does it matter? 1 challenge for electric vehicles. This is precisely why the Tesla pack weighs only twice more than the Leaf pack, yet delivers 3x more driving range. In other words, a Nissan Leaf using a hypothetical battery with cells at 700 Wh/L should be able to deliver a range of 120 - 140 miles, instead of the present 80 miles. I want one of those! Second, the use of large pouches makes it necessary to have dual levels of packaging, one at the module level, then again at the pack level. This adds unnecessary weight and volume to the pack. Look at the energy density for the module and the pack. For the module, it is down to 131 Wh/L, and for the pack, it is a dismal 49 Wh/L. ….this Leaf pack design does not scale well for longer driving ranges.
The 2003 Volkswagen Golf has an inline 4 engine. What kind of fuel does the 2003 VW Golf use? The 2003 Volkswagen Golf runs on regular unleaded. What is the curb weight of the 2003 VW Golf? The curb weight of the 2003 Volkswagen Golf is 2771 lbs. How long is the 2003 VW Golf? The 2003 Volkswagen Golf is 13 ft. 8.9 in. (164.9 in.) long. How tall is the 2003 VW Golf? The height of the 2003 Volkswagen Golf is 4 ft. 8.7 in. (56.7 in.). What ground clearance does the 2014 VW Beetle-Convertible have? The ground clearance of the 2014 Volkswagen Beetle-Convertible is 0 ft. 5.6 in. (5.6 in.). What ground clearance does the 2013 VW Jetta-Sportwagen have? The ground clearance of the 2013 Volkswagen Jetta-Sportwagen is 0 ft. 5.4 in. (5.4 in.). What ground clearance does the 2014 VW Jetta-Sportwagen have? The ground clearance of the 2014 Volkswagen Jetta-Sportwagen is 0 ft. 5.4 in. (5.4 in.). What is the front track of the 2003 VW Golf? The front track of the 2003 Volkswagen Golf is 4 ft.
