VW: e-Golf battery pack doesn’t need a liquid cooling system

Does an EV battery pack need a liquid cooling system? Automakers have different opinions. The Tesla Roadster and Model S have ‘em, the Nissan LEAF does not. Volkswagen initially designed its e-Golf with a liquid-cooled battery, but the production e-Golf, which is now on sale in Germany, and will arrive in selected US markets during the fourth quarter of 2014, relies on air cooling.

The company’s engineers have tested the e-Golf’s battery pack in places like Death Valley and Arizona, as well as cold-weather climates, and found no dramatic impacts on performance. VW’s Darryll Harrison recently told AutoblogGreen that the Panasonic lithium nickel manganese cobalt oxide cells used in the e-Golf had “the lowest self-warming tendency and the lowest memory effect of all cells tested. The need for a cooling system wasn’t there.”

Of course, this doesn’t mean that VW has given no thought to temperature issues. The company says it has developed a Battery Management Unit with an intelligent thermal control that allows the pack to remain within an optimal temperature window, and that waste heat is quickly directed into the chassis, away from the battery.

VW’s engineering goal for the e-Golf was to develop a highly efficient system, as opposed to one that focused on charge time or capacity. The e-Golf’s cells are designed for “gentle” charge and discharge, which helps to reduce heat, compared to cells designed for rapid charging. The lack of a cooling system also translates into weight savings.

On the other hand, the VW GTE plug-in hybrid (which debuted in February in Geneva, but won’t be sold in the US) does have a liquid-cooling system. According to Harrison, that’s because, whereas the e-Golf is designed to be efficient above all, the GTE is a plug-in version of the sporty GTI, and it will be tuned for performance.

 

(Headline updated 4/4/2014 19:00 EDT: “active cooling system” changed to “liquid cooling system.” Hat tip to Ule Amra)

Source: VW, AutoblogGreen

  • GuySmiley

    Hard to take the VW rep’s claims seriously when he talks about “memory effect” in Li batteries…

    • lasvegascolonel

      That’s what I thought. Nickel-metal hydride batteries like in the Prius have that, but lithium-ion batteries do not. It is already 109 degrees here in Las Vegas (June 29, 2014), I surely hope VW has thoroughly tested those batteries for a long time in Death Valley; otherwise, they’re heading down the same road Nissan did, though Nissan is now correcting that.

  • cw

    my Chevy Spark EV has liquid cooling… and is faster…. and cheaper….. and more efficient….. and fun to drive….. with same or better range…. heh. This VW nice car tho.

    • hinu7ycfgr5e

      Spark EV looks like ass, it has only 4 seats and it looks like ass. And it’s not particularly quick and it’s still FWD. Did I mention it looks like ass? Oh, and it quickly got superceded by the e-Golf (not that the e-Golf is a particularly good car either).

      They’re all compliance cars…

      • cw

        Well I have excellent taste and I think the Spark looks good. What cars do you think look good? When you say what looks bad, you should be able to counter with what looks good…..

        • hinu7ycfgr5e

          Hahah, excellent taste you say? xD Model 3 for one, looks much better. Bolt looks much better. Mazda 6 looks better.

          The proportions are just completely wrong. It looks like a kid’s drawing. It looks like a toy. Kinda like Honda’s new car they dare to call NSX. It’s a mess of a design. Lines don’t meet well, there’s is no design identity, the interior is a mess. The only way the interior is matching the design language is that it’s ugly.

          If you look at the original, you would see the same design language in the interior as well as outside. The old interior honestly looks better than the new one.

          It’s a car for 8 and 12 year olds. Have no class to it.

          If Spark was a stuffed animal for kids, it would be one of those goofy dinosaur cartoons for 3 year olds.

          • cw

            ok then.

          • hinu7ycfgr5e

            Alrighty then.

  • jstack6

    I’d go with the SPARK EV that is listed as a best buy for 2 years now, cost $5K less and has liquid cooling for 20-30 year battery life AND you can get DC Fast Charging.