Razer Blade 15 battery swelling

Hi, Despite always using the laptop on a stand and monitoring performance to prevent overheating issues, my battery just started swelling when using graphic intense games for a normal gaming session. Given I've already done all the things in the support video to try and avoid this problem, how can I get a new battery (it's definitely out of warranty)? I've replaced internal batteries on other laptops, so feel comfortable with somewhat complex installations... but need guidance on a) were to source a battery and b) if it's advisable for me to do it. Thanks for any help. Chris