Abstract: A method for producing electrolytic manganese dioxide with high compact density where electrolytic manganese dioxide pieces are milled in a classifying mill to produce first milled manganese dioxide particles where 30% of the particles are larger than 200 mesh and up to 95% of the particles are smaller than 325 mesh. The first milled manganese dioxide particles are milled a second time to produce manganese dioxide particles having a second particle size distribution. Also, an electrolytic manganese dioxide particle composition, wherein when the particle size distribution of the composition is plotted as a function of base-10 logarithm of the particle size, a first peak is centered at a particle size from 40-100 ?m and contributes a minimum of 20% of the area under the curve of the overall particle size distribution and a maximum of 45% of the area under the curve of the overall particle size distribution.