Trouble with my Toshiba satellite l300 power

Hello,

A week ago my Toshiba satellite pro l300 was working fine when all of a sudden it just shut down. When I turned the power back on the battery icon had a red x next to it. i got a new battery for my laptop and now the battery icon does not have the red x next to it. the problem that i am having is my toshibas battery is flashing orange and power flashing green. i cant get the new battery to charge. please can you help me as i have no idea what this means. thankyou.