Macbook Aluminum battery dies, "Service battery"

I have an Aluminum Macbook from May 2008. Since then, I had it fully restored in December 2011.

However, when I unplug the charger, the battery bar sometimes says "service battery" and usually the battery lasts no more than 30 minutes. (It loses about 1% every 30 seconds to 1 minute)... I run smcFanControl because otherwise my laptop heats up to 72+ degrees Celsius. It runs at 5400 rpm when hot, 3000 or so when stable. Could this be the cause?

Battery Information:

Model Information:

Serial Number: W092900EN13CB

Manufacturer: SMP

Device name: bq20z951

Pack Lot Code: 0000

PCB Lot Code: 0000

Firmware Version: 002a

Hardware Revision: 000a

Cell Revision: 0100

Charge Information:

Charge remaining (mAh): 1091

Fully charged: No

Charging: Yes

Full charge capacity (mAh): 1130

Health Information:

Cycle count: 152

Condition: Check Battery

Battery Installed: Yes

Amperage (mA): 365

Voltage (mV): 12585

Obviously the charge capacity is ridiculously small... Can I fix this? Any information would be greatly appreciated! Do I need to purchase a new battery? 😟