377 Battery Equivalent, Voltage, Size, Life & Uses

Last updated on April 3rd, 2024 at 11:22 am

It is a very small and popular non-rechargeable watch battery. It has a nominal voltage of 1.55 V, a capacity of up to 28 mAh, weighs 0.40 g, and is 6.8 mm in diameter and 2.6 mm in height. 

It has a shelf life of 4-6 years when stored at room temperature, decreasing to 1-2 years at high temperatures. The battery can be replaced with SR626SW, AG4, LR626, 377A, and 376 batteries.

It has a good battery capacity almost twice that of alkaline button cells. Since these are light in weight, the energy-to-weight ratio is very high. But are comparatively expensive due to the usage of silver.

Must read: Important Battery Terms & Characteristics Explained (with Examples)

What is a 377 battery?

377 terminals
377 terminals

This battery uses silver oxide as the cathode and zinc as the anode. Since they use alkaline electrolytes like sodium hydroxide (NaOH) or potassium hydroxide (KOH), the performance of batteries is usually compared with that of alkaline batteries.

These batteries are popular as a battery that finely adapts to high and low-discharge devices. Another advantage of these batteries is that they deliver stable output throughout their service life due to the multi-drain technology. Using potassium hydroxide as the electrolyte enables these batteries to operate even under heavy drains and at lower temperatures.

The discharge levels of 377 batteries are more stable than other alkaline variants and the self-discharge possibilities are relatively low. Apart from these advantages, using a small amount of mercury in these batteries prevails as a serious limitation.

377 battery equivalent

377 Equivalent batteries
377 Equivalent batteries

376, 377BP, GP377, D377, V377, E377, E377A, E377CA, 377A, 377X, are the most common replacements of 377 batteries.

The other equivalents of 377 include SB-AW, SR626SW, SR66, SR626, AG4, 606, LR626, LR66, SR628SW, and GP177.


377 Battery Specs
377 Battery Specs

The table lists the essential features of a 377 battery.

ShapeCompact and round
ChemistrySilver oxide
Nominal Voltage1.55V
Capacity28 mAh
Weight0.40 g
Operating Temperature-10 – +60 °C
Shelf Life4-6 yrs
377 battery features

The nominal voltage of the battery is 1.55 V. It weighs 0.40 g and is 6.8 mm in diameter and 12.6 mm in height.


377 batteries fall under coin cells. Thus they are ideal for small portable devices. The high and low drain capability of batteries makes them ideal for devices that need to be used continuously.

The small-sized medical devices like hearing aids, photoelectric exposure meters, digital thermometers, glucometers, heart-rate monitors, and blood pressure cuffs are some of the top applications of batteries.

The other applications include watches, keyless remote entry systems, small electronic toys, calculators, pagers, etc.


Are 377 and 376 batteries the same?

377 and 376 batteries have the same chemistry, which is silver oxide. But 377 is a low-drain battery and 376 is a high-drain battery. So they are used in the application based on this perspective. Since both batteries produce stable voltage, both of them are suitable for watches.

Are 377 batteries and 377A batteries the same?

Both these batteries differ in their chemistry. 377 has a silver oxide base, while 377A is alkaline. Although some applications specifically require 377A batteries, both 377 and 377A batteries can be used interchangeably.

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Ankit Negi

I am an electrical engineer by profession who loves to tinker with electronic devices and gadgets and have been doing so for over six years now. During this period, I have made many projects and helped thousands of students through my blog and YouTube videos. I am active on Linkedin.

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