Welcome to the Wyze User Community Forum @brumbleyg13515! 
This would be great, in theory. But we probably wouldn’t enjoy the price point for the cams that makes them so attractive. Also, there is precious little room inside the cam chassis for an additional charge controller \ power regulation board and batteries. Then there is the issue of the cam outliving the battery lifespan. And, it would only be able to operate by recording to the SD Card since the WiFi would also go down with the power.
But, others have already asked for this feature. Feature requests are posted in Wishlist category topics. Follow the link below, vote for the feature at the top, 
like some posts, and add your own reply and case use to keep the thread alive.