Buy OEM 2013 Subaru Part # 23700AA830 (23700AA620, 23700AA621, 23700AA831). Alternator

ALTERNATOR ASSEMBLY Alternator

Fits Legacy, Outback, Tribeca

Alternator
Your alternator replenishes your battery when your car is running. If you have a battery light, low charge warning, or your recently replaced battery already needs a jump, the alternator in your Subaru may need to be repaired or replaced.