Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
It is possible to replace the battery in a Golf Buddy Voice model rangefinder/GPS. The replacement battery is offered for sale in several places that I can list for you.
But, the procedure is not easy, and involves specific details of how to get the Golf Buddy Voice device apart exactly right, not to lose the buttons which tend to come off, and similar details.
Would you prefer, with that in mind, to send the Gold Buddy Voice off to have the battery replaced, rather than trying to do the task yourself?
Whichever you choose, let me know and I will guide you in the specifics of each.