This question is an exact duplicate of:
Is it possible to replace a battery for headphones? I would like to replace a 052030 li po battery with a Nokia BL-5C Lithium Ion battery. The li po battery is rated at 130 mAh with 3.7v. The Lithium Ion battery, on the other hand, is 1 Ah with 3.7v.
Thank you for your help.