We hope to be able to offer additional batteries to our SwiftPaws accessory items soon! But in the meantime, you might find compatible batteries at a local home / hobby store or online. Here’s one example. (Image on left)
Your SwiftPaws Home uses an 11.1V 1500mah 3-cell 25c LiPo battery that has an xt60 connector and does not have a discharge rate of over 60c. It has an average of 150–250 cycles (charging and discharging is one cycle).
Note, you can purchase compatible batteries that have a larger capacity which will last longer. They might not fit perfectly into the compartment but that shouldn't affect performance. You just want to be sure you're getting an 11.1v battery that has an xt60 connector and does not have a discharge rate of over 60c. This is one example of a compatible battery with a larger capacity. (image on right)