Early reports have said that the Audi Q5 hybrid will use the Nickel metal hydride batteries of the VW Touareg hybrid and Porsche Cayenne hybrid but I can confirm that according to Audi’s latest press reports as of November 11, 2010,
the Audi Q5 hybrid will use lithium ion batteries.
The parallel hybrid system allows electric only driving up to 37 mph for up to 1.86 miles with a maximum speed of 62 mph on electric drive alone! (The electric only range will obviously go down at those speeds). The battery weighs 84 lbs and takes up a volume of 6.9 gallons which is small enough to fit in the back of the Q5 chassis. It’s made up of 72 cells, at 266 V its nominal energy is 1.3 kWh and output of 39 kW.
Compared to the NiMH battery pack in the VW Touareg/Porsche Cayenne, which has 240 cells with 288 V, a a battery capacity of 75 Ah, energy density of 1.7 kWh, and peak power output of 38 kWh, as expected, the Q5 hybrid’s more advanced li-ion battery is slightly lighter and with many fewer cells.
Much like the Touareg hybrid and Cayenne hybrid, the battery pack is air cooled with the interior air fan. However, the Audi Q5 hybrid also adds liquid cooling if it gets too hot. Interestingly enough, the battery coolant is also coupled to the interior climate heat control. The coolant lines are visible in the pictures below.