The inspiron 13 battery replacement can be done fairly easy, just follow the following step by step video:
You will need two scredrivers: one phillip and a torx-6.
First, remove the bottom cover by unscrewing the 9 screws
then pry open the bottom cover using a thin metal or platic, be careful not to scratch the laptop
after removing bottom cover, unscrew the battery and disconnect the cable off the motherboard
put in the new battery, which you can purchase here: https://amzn.to/3mU1b38
put the screws back in and connect the battery back to the motherboard
put the bottom cover back and you’re good to go.