Batteries for hearing aids provide a consistent source of power that enables your hearing aid to work properly. To get the most out of your devices, you need to have the correct batteries. Hearing aid batteries come in a wide variety, making it difficult to select the right one for your specific hearing aid and hearing loss.Batteries for hearing aids provide a consistent source of power that enables your hearing aid to work properly. To get the most out of your devices, you need to have the correct batteries. Hearing aid batteries come in a wide variety, making it difficult to select the right one for your specific hearing aid and hearing loss.