LR41 Battery Equivalents and Replacements
LR41 battery is a very popular non-rechargeable button/coin cell battery, manufactured by practically all battery brands and often labeled using different labels, leading to certain confusion.
There are also several battery chemistries used for the batteries of this size, offering different features and discharge characteristics.
LR41 Battery Features and Specifications
LR41 battery is a non-rechargeable alkaline battery with physical dimensions of (D x H) 7.9 x 3.6 mm (~0.3110 x 0.1417 inches).
The nominal voltage of the LR41 battery is 1.5 volts with a cutoff voltage of 0.8 volts. Nominal capacity varies depending on the battery model and use and is usually between 25 and 32 mAh.
Note: Some manufacturers print on the battery package nominal voltage of LR41 batteries as 1.55 volts and not 1.5 volts - this is not wrong, just 1.55 volts is the voltage of fresh (brand new) alkaline LR41 battery with no load of any kind. After some time, even with no load, their nominal voltage drops to 1.5 volts or even lower.
LR41 battery features other labels as well, including LR736, AG3, and similar - often some labels used for LR41 battery are used for SR41 battery and vice versa.
However, the biggest confusion for end-users is the fact that other chemistries are used for making batteries of this size, including silver-oxide and zinc-air, while mercury-oxide batteries are now obsolete due to the mercury content.
Silver-oxide 7.9 x 3.6 mm batteries are usually labeled as SR41, SR736, SR736PW, SR736SW, SG3, AG3, 192, 384, 392, although other labels are used as well.
SR41 battery features a nominal voltage of 1.55 volts, a much more stable output voltage than the LR41 battery, and a capacity of 38-45 mAh.
Thanks to the stable output voltage, SR41 batteries, often labeled as SR41SW batteries or SR736SW batteries, are used for powering sensitive electronics, typically wrist and similar watches.
Most modern SR41 batteries are so-called multi-drain batteries, suitable for powering low-current devices (for example, wristwatches with no LED lights or alarms) and devices that periodically require relatively strong currents (for example, wristwatches with LED lights and/or alarms).
However, some manufacturers still offer both 'low-drain' and 'high-drain' SR41 batteries, so choose according to your own needs and requirements.
Zinc-air 7.9 x 3.6 mm batteries are usually labeled as 312, ZA312, Brown Tab, PR41, 7002ZD, while other labels are used rarely.
312 battery features a somewhat lower voltage of 1.40-1.45 volts, but they also feature a much larger capacity, usually around 160 mAh.
While LR41 and SR41 batteries are used in various electronic devices like calculators, watches, remote controls, toys, and similar, 312 batteries are almost exclusively used in the hearing aid devices - when the protective tab is removed, air enters the battery and the battery is activated.
Since 312 battery uses 'wet' electrolyte, the battery 'dies' when it gets discharged or when the electrolyte dries out - after activation, hearing aid batteries operate few weeks, rarely much more than that.
The following comparison chart lists the most important features of the chemistries used in 7.9 x 3.9 mm button/coin cell batteries:
|Capacity||25-32 mAh||38-34 mAh||~160 mAh|
|Voltage||1.5 volts||1.55 volts||1.4-1.45 volts|
|Note||Output voltage drops over time||Very constant voltage||Slightly lower voltage, large capacity|
|Typical Labels||LR41, LR736, AG3||SR41, SR736, SR736PW, SR736SW, SG3, AG3, 192, 384, 392||312, ZA312, Brown Tab, PR41, 7002ZD|
Can One Replace 312 Battery with LR41 or SR41 Battery?
Zinc-air 312 hearing aid battery has ~5x larger nominal capacity than LR41 or SR41 battery and somewhat lower nominal voltage.
But, zinc-air batteries are often discharged with much stronger currents than LR41 and SR41 batteries usually, 2-10 mA vs. 0.01-0.1 mA.
Thus, if LR41 and especially low-discharge SR41 batteries are used instead of 312 batteries, their actual capacity is going to be far below their 'nominal' capacity.
High-discharge SR41 batteries can be used instead of 312 batteries, but they will also experience a capacity drop.
For short - don't replace your 312 batteries with LR41 and SR41 batteries. Your hearing aid device will probably operate for a short period of time, but ... Should you decide to actually replace for some reason your 312 battery with LR41 or SR41 battery, before doing that, check the hearing aid Owner's Guide - maybe there are other reasons why not to do it...
LR41 and SR41 Batteries Safety Issues
Modern alkaline and silver-oxide batteries are made using non-toxic materials and they don't contain mercury, cadmium, and similar hazardous materials.
Nonetheless, LR41 and similar batteries should be kept away from kids and pets - they are shiny little objects that look interesting and that can easily get swallowed.
Although they are not toxic, in the contact with body fluids, they can start electrolysis that can produce harmful compounds that can cause internal chemical burns.
If LR41 or any similar battery gets swallowed, contact your nearest emergency center, explain to them what happened and act according to their instructions.
Long Story Short: If You are looking for a new LR41/SR41 battery, go for the battery from reputable brands, tried and tested by many users.
For sensitive electronics, the SR41 battery is a better choice since it offers more stable voltage and larger capacity. Also, the shelf life of SR41 batteries is longer than the shelf life of LR41 batteries, sometimes by 50-100%.
LR41 batteries are cheap and reliable batteries, often used in toys and devices that are not sensitive to the voltage drop during operation. Also, they are cheaper than SR41 batteries.
312 (Brown Tab) hearing aid batteries after activation last few weeks, rarely more - if they are used on a daily basis, they practically never die due to the electrolyte getting dry.