mfennell said:
PMC2015 said:
Just a point of clarification, VW didn't work with LG Chem on the battery, it was Panasonic:
https://media.vw.com/model/pack/92/
Oops. You are absolutely correct. Audi/VW does work with LG Chem but the e-golf and A3 e-tron use Panasonic cells.
Not just any Panasonic cells either, the chemistry on them is different, it is DESIGNED for gentle charging and discharging cycles.
For the record, we've included the detailed statement that Harrison emailed AutoblogGreen below.
Generally speaking, regarding the system, it's important to note that the e-Golf was designed with efficiency in mind. The battery pack utilizes ultra-efficient lithium-ion cells that deliver 25Ah per cell with an energy density of 59Wh per lb. The pack is comprised of 264 cells, packaged into 27 modules (of either 6 or 12 cells) delivering 323 volts and weighing in at 700 lbs. As it relates to battery temperature, VW has developed a Battery Management Unit with an intelligent thermal control that allows the pack to remain within an optimal temperature window, helping to maintain performance and range in a variety of temperatures. This system allows the e-Golf to operate, even in more extreme temperatures, without the need of a cooling system and without dramatic impacts in performance based on testing.
In terms of the battery pack, the engineering goal was to develop a highly efficient system as opposed to one that focused on charge-time or capacity (like some of our competitors). In partnership with Panasonic, VW utilizes a lithium-ion cells designed for gentle charge and de-charge during use which helps to reduce heat and energy consumption often associated with cells designed for rapid charging and de-charging. Our engineers refer to them as "marathon cells." Additionally, without a cooling system weight savings are achieved which aides in overall efficiency of the vehicle. Due to the efficiencies achieved, minimal waste heat is created during operation (i.e. during fast charging) and is quickly directed by the battery metal structure into the chassis, away from the battery, helping to prevent extreme temperature conditions inside the pack.
Our engineers tell us that the e-Golf has passed various long-term engineering evaluation milestones in desert temperatures and cold weather climates, without the necessity of a cooling system.
From this link... http://www.autoblog.com/2014/03/31/vw-e-golf-will-not-have-active-cooling-system-lithium-battery/
So drive accordingly, like an old man, this is not a high performance E-car, save the full throttle applications for the Tesla. Also, probably a good idea to forget about 20 minute charges to 80% State of Charge with SAE adapters. Slow and steady 7.2KWh charge rate, or less, over 3 or more hours, is where it's at for this battery pack on the e-Golf.
Oh, and Volkswagen, you are on notice... I am glad your e-Golfs "passed" your long term engineering evaluation milestones.... I hope you did a better job on the programming on the e-golf than you did "passing" the CARB NOX requirements with a "cheat", for emissions, to sell TDi's touting "clean diesel". You made the bed in which you now sleep, Volkswagen.
That chemistry, it turns out, is lithium nickel manganese cobalt oxide (NMC) in cells from Panasonic. These cells had "the lowest self-warming tendency and the lowest memory effect of all cells tested
More info about choice of "fuel tank" chemistry on our e-golfs.
http://batteryuniversity.com/learn/article/types_of_lithium_ion
In typical VW fashion, as they are ruled and run by frugal, cheap accountants...
NMC is the battery of choice for power tools, e-bikes and other electric powertrains. The cathode combination is typically one-third nickel, one-third manganese and one-third cobalt. This offers a unique blend that also lowers the raw material cost due to reduced cobalt content In other words, Volkswagen buys cheap batteries. We will see how they hold up to 8 years and 100,000 miles to 70% charge of original.
loving the car though, both looks and performance wise.