As of 2015, hearing aid batteries manufactured by Power One, Duracell and Rayovac are the most popular according to customer rating. Positive reviews of Power One, the brand rated highest most frequently, indicate a superior battery life.
Hearing aids all use similar parts but vary greatly in price, size, special features, and how they are positioned within the ear. User demand focuses on smaller models that are able to be worn discretely, but these might not have the required power capacity to be effective. Zinc, mercury-free and rechargeable batteries are among the highest-rated hearing aid batteries with additional features, according to Amazon.com reviewers.