I have a lot of things that use batteries. Shopping carts, watches, controls and other nonsense. When I go to buy batteries at the supermarket I scare with the price. I recently found, in promoting cheaper, By R$11,90 8 batteries.
A great idea is to buy a tube of 60 batteries, as shown below. Out between 40 and 45 real on eBay including the freight. The cell value is around 75 cents, much better than a real and little at the best price from the supermarket.
The batteries are packaged 4 in 4, and last quite. Just keep carefully.
This is the second time that I buy batteries on eBay. Next I'm going to buy AAA along with AA for trying to save on freight. But that should take, Why use 60 batteries will not be overnight!