Replacing the Plastic Contacts Guard of Hero4 Battery

Referring to an Original GoPro Hero 4 Battery.

The Battery has a plastic thingy that guards the contacts and "locks" them from moving and touching.

This guard fell out while removing the battery from an external charger.

I haven't been able to replace it yet.

Any ideas how to do it?

Is there a handy tool to be used?

Must the battery be disassembled?

Photos:

https://flic.kr/p/wg1oBx

https://flic.kr/p/wxv9kt

Thanks,

Alon