You have to follow the link to Design News to get to the "money quote":
Aluminum-air also differs from lithium-ion in that it is not rechargeable. That's why the company is suggesting that its batteries be used in a hybrid arrangement, in which drivers would employ lithium-ion on a daily commuting basis, while aluminum-air would serve only on those days when greater range is needed. In such an arrangement, the aluminum-air system would last about a year before needing to be "refurbished" at an unknown cost.
So, great, you're carrying around extra weight every day hoping you'll not need it instead of driving a lighter car with more daily range.