I've had this problem throughout my life. Especially after long batting cage sessions. My solutions have been Easton Adult HS VRS Batting Gloves that have a pad right there on the outside of the palm (I assume specifically for this issue). I haven't had the blister since I've worn those, but the Easton model is discontinued you can try searching Amazon for whatever places have in stock. Also the last year I have had one of those rubber Bat Ring/Power Pads on the knob of my BP bat and it seems to have cushioned the knob enough to stop the problem as well.
EDIT: Here's a Rawlings glove with the same type of palm/heel padding