Business briefs

Marts

US stocks ended flat yesterday but capped the best week for Wall Street bulls in almost three years. For the week, the S&P was up more than 7 percent.

Volt battery

GM hasn’t ruled out making changes to the Chevy Volt plug-in hybrid’s lithium-ion battery in the wake of fires that occurred following collision tests, said Mary Barra, GM senior vice president of global product development.

Bay State

GMAC Mortgage will stop buying new mortgage loans in Massachusetts that were made by other correspondent lenders and wholesale brokers.

Geithner trip

Treasury Secretary Timothy Geithner will travel to Europe next week for meetings with political leaders and central bankers as they prepare for a summit on the continent’s debt crisis.

Ticketmaster

Ticket buyers who used Ticketmaster between Oct. 21, 1999 and Oct. 19, 2011, can expect a refund. In a proposed class-action settlement, the ticket Web site is being asked to refund $1.50 for each ticket order because it profited from questionable fees.