VW MEB 2020

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Typical EV battery made of 6720 Li+ cells managed by eight control modules. Each cell has a capacity of 3.54Ah, up to a total nominal energy storage of 100kWh (3.54Ah x 4.2V x 6720 cells).

The series of 96 rows, each made of 70 cells in parallel, add up to a battery voltage of 403.2V (96×4.2V), with a capacity of 248Ah (100kWh). To learn more, check out the MAX17843EVKIT, the evaluation kit that allows you to assess this part for your next automotive design.

… all the control modules communicate serially with a central microprocessor via IC1. Isolation is required between the microprocessor and the first module, and from one module to the next. The data link must reliably operate in noisy high-power battery environments, where both the high dV/dt supply noise and common-mode current injection (induced by electromagnetic fields) are present.

The MEB / ID chassis can cover a wide range of vehicles, from the compact class/SUVs to large B-segment 7 seat sedans, vans.

The MEB architecture is designed to cover the full market spectrum for the VW brand. VW Buzz Wheelbase – 3,300 mm, Length 4,942 mm, Width 1,976 mm. “The modular electric drive matrix (MEB) is arguably the most important project in the history of Volkswagen”, says Thomas Ulbrich, Member of the Board of Management responsible for E-Mobility. Wheelbase & height of flat floor battery >> casing of battery modules >> cells.
For the MEB’s battery strategy, VW will offer a standard pack that will top 200 miles (322 km) of range in the U.S. driving cycle and at least one upgrade extending that to about 300 miles (483 km). Charging time is as little as 30 minutes for 80% of the maximum range, the automaker says.
The battery pack’s lithium-ion cells will be prismatic, at least initially, meaning Panasonic Energy is the likely supplier. Panasonic, the only major EV battery maker producing prismatics, already provides cells to Audi, Porsche and Tesla and also is Tesla’s partner in a new battery plant in Nevada, which presumably would be a candidate to supply any U.S. MEB production.
However, Erb says the liquid-cooled packs could accommodate pouch-type cells, and that VW will have to be prepared to adjust sourcing depending on supply-chain issues. “You have to be flexible,” he says. “But if you localize the product…you are going to change parts. You have to. This also would apply to the (battery) cells, as far as we see at the moment.
“And we’re already planning for the next-generation of batteries,” he adds. “Sooner or later we could switch to solid-state batteries – this is what the market expects and what we’re already working on.”

2018: The initial 48-62kwh MEB capacities will have 7-9 modules, with 12 modules for the 82kwh extended pack. The cell modules are about the size of a low-set shoebox, with long pouches oriented lengthwise or shorter prismatic cells oriented cross-width. Under the supply chain, as it was conceived, pouches will always come from LG Chem and prismatic from Samsung SDI and they confirmed that there are 24 cells per module, at least in the case of pouch cells. >> 6.86kw/module, 286W/cell (~3.6v80Ah)

In the case of the Volkswagen ID.3, the flagship model, the pack is described as follows:

• modular architecture with up to 12 modules for the full 550 km/342 miles (WLTP) range
• ID.3 options: 45 kWh (330 km WLTP), 58 kWh (420 km WLTP), 77 kWh (550 km WLTP)
• each module consists 24 individual lithium-ion cells
• operating voltage is up to 408 V
• maximum DC fast charging rate is 125 kW
• the battery has a liquid thermal management system
• to keep the weight low, battery-pack housing is made from aluminum with an integrated crash frame
•  the 12-volt direct current electrical system is supplied with low voltage using a DC/DC converter
• in a normal alternating current system, the battery is charged with a maximum charging power of 11 kW and in a direct current system with a charging power of up to 125 kW