Giglap

After seeing some videos of tritium tubes paired with solar cells to make long lasting but very low power batteries I wondered how to increase the power I'm guessing that for safety, the tritium in readily available tubes is at one atmosphere. It seems that raising the pressure to say two atmospheres would significantly increase the light output. 3 ATM? If true then at some point I expect that the phosphorus would 'max out', but just hypothetically wouldn't raising the pressure (the amount of tritium in the tube) increase the radiation within the tube and hence the brightness of the phosphorus coating? Although I would be interested in hearing better alternatives, I'm still curious if my premise is correct. Thanks, -Jim