I suggest you to use sticky gum. Protective film can't be covered on non-sticky gum. You'd better wipe up the gum when you use it.
This is a very simple method. But I assure you it works. Use damp towel to wipe the bat to clean it. And then coat it with protective film when it's still damp.
You can use adhesive plastic protective film. This kind of film can used on both sticky gum and non-sticky gum. I recommend this type. It can increase the stickiness of the sticky gum. If the gum is not sticky any more, it can help get it sticky again. If the film is not adhesive any more, you can wash it with water and then dry it, and it will be adhesive again.
