The hearing aid battery life calculator gives the hours and days of use per cell, the number of cells per year and the yearly cost from the battery size, the current drain, the hours of use per day and the price of a cell.
How the calculation works
- Choose the battery size.
- Enter the current drain, the daily use and the price.
- Read the days per cell and the yearly cost.
Example
A size 312 cell holds about 180 mAh. In an aid that draws 1.3 mA, it lasts 180 / 1.3 × 0.9 = 125 hours. At 14 hours a day this is 8.9 days. A year then needs 365 / 8.9 = 41 cells, and at $0.80 a cell the cost is 32.80.
Why it matters
The calculator helps hearing aid users, caregivers who manage the aids of a relative, audiologists who advise on the choice between disposable cells and a rechargeable aid, and anyone who budgets for hearing care.
Good to know
The size of the cell is set by the size of the aid: the smallest aids use size 10, behind-the-ear and in-the-ear aids use 312 or 13, and powerful aids use 675. A larger cell lasts longer but needs a larger aid. The life also depends on the features, since wireless streaming of audio can double the drain, and on the environment, because cold weather reduces the voltage. Zinc-air cells are activated by the air, so they should be kept sealed until use, and should not be stored in a refrigerator or in a pocket with metal objects. Used cells should be taken to a collection point since they contain small amounts of metals. Rechargeable aids with lithium-ion cells avoid the need to change cells and last a day, but need charging each night and a replacement of the cell after some years. The calculator gives a typical estimate, and the real life is checked by noting the day of each change.
Related tools
The NAL-R calculator treats the gain of an aid, the QuickSIN calculator treats speech in noise, the hearing aid cost calculator covers the full cost of ownership and the ear canal calculator treats the acoustics of the ear.