Here’s an extremely simple test to verify if your alkaline batteries are still good: just drop them from a low height on a hard surface: The good batteries will stay down while the bad ones will bounce like a man on a pogo stick. Please note that this test will also work for AA, AAA, C, D and 9 Volt alkaline batteries.
A non-rechargeable alkaline battery begins life using zinc powder mixed into a gel containing a potassium hydroxide electrolyte separated from a paste of manganese dioxide powder mixed with carbon powder using a porous membrane. To minimize hydrogen outgassing an extra measure of manganese dioxide is added. As the battery discharges manganese dioxide powder changes to manganese oxide causing the powdered granules to bond both chemically and physically. This packed-sand consistency reduces the antibounce effect exhibited by the gel mixture when the battery was fully charged.