SRS lamp glows red!

Hello, dear, I drive a Mitsubishi Galant 2000. For a few days the SRS lamp has been shining red. 2 weeks ago the battery was empty and I removed the battery, brought it to the workshop to recharge and reinstalled the next day. Then I only started for a short time, it went out and made it out again. The next day I had to start 10 times before my car wanted! Since then the red SRS lamp lights up, but I can drive by car. What could be broken and how much we d it cost me :-)???! Maybe I should mention that my car is almost 10 years old. Who can help? Who knows? I’m very excited. Thank you.