Shares of A123 Systems Inc., a Waltham-based maker of batteries for electric cars and utilities, rose after announcing a contract to supply power-storage systems to a U.K. grid operator.
A123 gained as much as 9.6 percent and was up 8.5 percent to $2.04 in mid-morning trading in New York after saying it would provide six of its grid battery systems to Northern Powergrid, a unit of Iowa-based MidAmerican Energy Holdings Co. that supplies power to more than 3.8 million customers in the U.K.
The storage systems will manage fluctuations on the grid and will be in operation by the end of this year, according to a statement today.
A123 yesterday fell 24 percent to $1.88, the biggest decline since September 2009, after its largest customer, Fisker Automotive Inc., stopped work on a factory and an analyst downgraded its shares.
Fisker said Feb. 6 that it fired 26 employees and stopped work at the factory it’s developing in Wilmington, Del., to make plug-in electric vehicles after the US Energy Department blocked access to a federal loan.