I used walmart batteries, size 31 I believe (maybe 29, can't remember)... I just replaced the first battery this year which was 5 years old... The other is also 5 yrs old and going strong. I really don't think there is a huge difference in name brands as long you keep them charged year round. I am sure there will be some folks insisting that this brand or that grossly out performs the other, but unless you go to gel batteries, I really don't think there is much... I have never ran out of battery using my terrova, or even close for that matter and I have fished for hours in the wind using spot lock... or trolled for hours.. I suppose it can be done, I just haven't been able to.