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What is a SR626SW Watch Battery?
Features of SR626SW Battery
Specifications of SR626SW Battery
Advantages of Using SR626SW Battery
SR626SW Battery Equivalents
Differences between SR626SW and LR626 Batteries
Applications of SR626SW Battery
How to Replace an SR626SW Watch Battery?
How to Properly Store and Dispose of SR626SW Battery?
Tips for Choosing the Right Battery Replacement
Frequently Asked Questions

SR626SW 377 Watch Battery Equivalents and Replacement

02 September 2025 11242

The SR626SW, also known as the 377 battery, is a non-rechargeable silver-oxide button cell. Wristwatches, calculators, medical devices, and small electronics are widely use this battery.

Its dismension is 2.6 x 6.8 mm. This article will introduce its features, specifications and equivalents. At the same time, you can learn tips for storing and disposing of this battery.

What is a SR626SW Watch Battery?

The SR626SW, also known as the 377, is a small, button-shaped silver oxide battery. The “SR” in its name means silver oxide chemistry. “626” refers to its size, which is 6.8 mm in diameter and 2.6 mm in height. The “SW” shows that it has low drain.

Wristwatches and other compact electronic devices are widely use these batteries. This battery provides a stable voltage output of 1.55 volts. Therefore, it is ideal for clock and watches that require stable power supply.

Features of SR626SW Battery

Stable Voltage Output: 1.55v

Compact Size: A diameter of 6.8 mm and a height of 2.6 mm

Silver Oxide Chemistry: Better stability and longer life

Low Drain Design (SW type)

Non-rechargeable

Long Shelf Life: 3–5 years

Low risk of leakage

Wide Compatibility: Easy to find replacements, such as 377, D377, SR66.

Specifications of SR626SW Battery

Parameter	Specification
Battery Type	Silver Oxide (SR)
IEC Code	SR626SW(also known as 377,depending on the manufacturer)
Diameter	6.8 mm
Height / Thickness	2.6 mm
Nominal Voltage	1.55 V
Capacity (typical)	25–30 mAh
Drain Type	Low Drain (SW)
Operating Temperature	-10°C to +60°C
Typical Shelf Life	3–5 years
Terminal Style	Flat positive (+) and negative (-) terminals
Common Equivalents	377, D377, SR66, AG4, 376/377
Applications	Wristwatches, calculators, medical devices, toys, small electronics
Manufacturers	Energizer, Renata, Maxell, Sony, Panasonic, Duracell, Seiko

Advantages of Using SR626SW Battery

Stable Power Output – Provides a stable 1.55V output.

Longer Lifespan – Compared to alkaline equivalents, silver oxide chemistry offers a longer service life. This reduces the need for frequent replacements.

High Accuracy for Watches – Its steady voltage helps maintain accurate timekeeping.

Compact and Lightweight – 6.8 × 2.6 mm

Low Leakage Design – This helps protect sensitive electronic circuits inside watches and instruments.

Wide Compatibility – Interchangeable with multiple equivalents (e.g., 377, D377, SR66).

Low Self-Discharge – This means it loses very little power just sitting on a shelf.

Environmentally Safer – Modern button cell SR626SW is mercury-free.

SR626SW Battery Equivalents

The coin battery SR626SW equivalent code is 377. It may be labeled with different part numbers, depending on the manufacturer. Because different brands use their own naming systems.This can be vary useful when looking for replacements.

Here is a full list of watch battery 376 battery equivalents:

Brand / Standard	Equivalent Code
IEC Standard	SR626SW
Energizer, Renata, Duracell, Panasonic, Maxell, Sony	377
Maxell	SR626SW
Duracell	D377
Sony	SR626SW
Panasonic	SR626SW
Seiko	SB-AW
Varta	V377
Renata, Varta, EEMB	SR66
Seiko, Maxell	SW66
Panasonic	G6
Varta	AG4
Rayovac	626
Toshiba	S626E
Varta	CA36
Energizer, Rayovac	L626

Key points:

Physical Size: All listed battery models share the same size of 6.8 mm in diameter and 2.6 mm in height. They are interchangeable and fit the same battery compartment.

Main Chemistry: Most of the equivalent models (SR626SW, 377, SR66, SW66, G6, AG4, 626, S626E, CA36, V377, D377) use Silver-Oxide chemistry.

Stable Voltage: All Silver-Oxide models provide a stable 1.55 volts.

L626(Exception): It uses Alkaline chemistry and provides a lower, 1.5 volts. It is not a suitable for devices designed for a silver-oxide battery.

When replacing your battery, focus on the chemistry and the physical size. Silver-Oxide batteries are marked with an "S" in SR626SW. Well-known brands like Energizer, Renata, Panasonic, Maxell, and Duracell make good quality versions.

These SR626SW replacement batteries are labeled with one or more of these numbers. Always check that the battery voltage is 1.55V. This ensures you have the correct type of silver oxide.

Differences between SR626SW and LR626 Batteries

The battery SR626SW and LR626 share the same physically size. So they are often confused as direct replacements.

However, they differ in chemistry, performance, and lifespan. This directly impacts how well they work in devices like watches.

Feature	SR626SW (Silver Oxide)	LR626 (Alkaline)
Chemistry	Silver Oxide (SR)	Alkaline (LR)
Nominal Voltage	1.55 V (stable output)	1.5 V (drops over time)
Voltage Stability	Very stable throughout life	Declines steadily as battery discharges
Capacity	~25–30 mAh	~15–20 mAh
Lifespan in Watches	2–3 years (longer)	6–12 months (shorter)
Best For	Precision devices (watches, medical instruments)	Low-cost, short-term use (toys, small gadgets)
Cost	Slightly higher	Lower upfront cost
Leak Resistance	High (better protection)	Lower, more prone to leakage
Standard Codes	SR626SW, 377, D377, SR66	LR626, AG4

⚠️ While the LR626 can physically replace the SR626SW, its performance and lifespan are not as good as the button battery SR626SW. For watches and other precision devices, SR626SW is the recommended choice.

Applications of SR626SW Battery

The watch batteries SR626SW are widely used in small, low-drain electronic devices. Because it is small in size, has stable voltage and long life. Its applications include:

Wristwatches and pocket watches (This is the most common use)

Small calculators

Digital thermometers

Laser pointers

Electronic toys

Fishing lures with LED lights

Key fobs

Digital pedometers

Some medical devices (like glucose meters)

Hearing aids (some models)

How to Replace an SR626SW Watch Battery?

Tools You’ll Need:

Watch Case Opener: This can be a specific tool for your case back type. Using the wrong tool can scratch your watch.

Tweezers: Preferably plastic or non-conductive tweezers.

Plastic Prying Tool: A guitar pick or a plastic spudger can help pop open a snap-back case.

Magnifying Glass: Helpful for seeing the small parts and the battery's polarity (+/-) markings.

Soft, Clean Workspace: A microfiber cloth to place the watch.

Step-by-Step: Replacement Battery SR626SW

1

Turn Off and Place the Watch in a Safe Position
Work on a clean, flat surface with good lighting. Place the watch face down on a soft cloth.

2

Open the Watch Case Carefully

For Screw-Back Cases: Use a watch case wrench that fits the notches on the back. Turn it counter-clockwise to unscrew.

For Snap-Back Cases: Look for a small notch on the edge of the case. Insert your plastic pry tool into the notch. And gently twist to pop the back off.

3

Locate and Remove the Old Battery
Once the back is off, you will see the watch movement. The small metal clip holds the battery. Note which side is facing up (+). Use plastic tweezers to carefully lift the battery out.

4

Insert the New Battery with Correct Polarity
Look at the new battery: the flat side with the writing is almost always the positive (+) side. The rounded, shiny side is the negative (-) side. Place it into the clip exactly according to old battery'position. The positive side must face up.

5

Close the Case and Test the Watch

For a snap-back case, align the back. And press down firmly with your thumb until you hear a click.

For a screw-back case, place the back on. And turn it clockwise with the wrench until it is snug. Do not over-tighten.

Once closed, set the time and date and ensure all functions are working.

Safety Tips

Avoid using metal tweezers to prevent shorting the battery.

Do not force the case open.

Dispose of the old battery properly in accordance with local regulations.

Wash hands after handling old batteries to avoid contact with any residue.

Keep Away from Children: These batteries are a choking hazard and can be very dangerous if swallowed.

How to Properly Store and Dispose of SR626SW Battery?

Proper Storage Tips

Store in a Cool, Dry Place: Keep batteries away from heat, moisture, and direct sunlight. Ideal storage temperature is between 10°C and 25°C.

Keep in Original Packaging: Store unused batteries in their original packaging to prevent short circuits.

Avoid Contact with Metal Objects: Do not store batteries loose in drawers with coins or keys. Because this can cause short-circuiting.

Separate New and Used Batteries: Keep fresh batteries apart from used ones to avoid accidental mixing and leakage.

Avoid Freezing: Do not store batteries in the freezer; extreme cold can damage the battery chemistry.

Proper Disposal Tips

Do Not Throw in Regular Trash: Silver oxide batteries contain metals that can harm the environment if disposed of improperly.

Use Recycling Programs: Take used batteries to designated battery recycling points, electronic stores, or hazardous waste collection centers.

Prevent Leakage During Disposal: Tape the terminals of used batteries before disposal to avoid short-circuiting and leakage.

Follow Local Regulations: Always comply with local laws regarding battery disposal and recycling.

Tips for Choosing the Right Battery Replacement

By choosing the right replacement battery, your watch or device will function reliably and last longer. Here are some practical tips:

Match Size and Chemistry

Always choose a battery with the same size and chemistry. Avoid using alkaline equivalents (LR626) in precision devices. Because they have shorter life and unstable voltage.

Check Brand and Quality

Choose a reputable brand such as Energizer, Renata, Duracell, or Sony. Because high-quality batteries are more reliable, last longer, and lower leakage risk.

Verify Battery Codes and Equivalents

Look for compatible codes like 377, D377, SR66, or AG4. In order to maintain proper device performance, ensure the replacement is a silver oxide type.

Check Expiration or Manufacture Date

Choose fresh batteries with a long shelf life. Avoid expired or old stock to prevent early power loss.

Consider Multi-Packs

If you frequently replace batteries, buying multi-packs can save cost and ensure you always have spares.

Purchase from Trusted Sellers

Buy from authorized retailers or reputable online stores to avoid counterfeit batteries.

Environmental Considerations

Check for mercury-free batteries, which are safer for the environment.

SR626SW (377) watch battery is a reliable power source for watches and small electronic devices. Its stable voltage, long lifespan, and compact design make it ideal for precision instruments. While its wide range of equivalents ensures easy replacement across different brands.

Whether you are replacing a watch battery yourself or stocking spares, selecting the right SR626SW button cell battery ensures accurate timekeeping, reliable operation, and safety for both your devices and the environment.

Frequently Asked Questions

Are 377 and sr626sw the same?

Yes, a 377 battery is the same as an SR626SW battery. In watch batteries, the abbreviation for SR626SW is 377.

Can i use sr626sw instead of sr621sw?

No, SR626SW and SR621SW are not the same. The SR626SW is thicker (2.6mm) than the SR621SW (2.1mm).

What battery is compatible with sr626sw?

Batteries AG4, LR626, 377, or 377A are typically compatible with SR626SW.

What size battery is sr626sw?

The battery 377 SR626SW has a diameter of 6.8 mm and a thickness of 2.6 mm.

Where can i buy a sr626sw battery?

You can buy an SR626SW 377 battery from Amazon, eBay, or Alibaba, or from electronics and watch repair stores.

What does SR626SW mean?

The SR626SW is a silver oxide button battery. "SR" refers to its silver oxide material. "626" refers to its dimensions (6 mm diameter, 2.6 mm height). "SW" indicates that it is a low-drain battery.

Are SR626 and LR626 the same?

No, LR626 and SR626 batteries are not the same. The key difference is: SR626 batteries are silver oxide. They offer longer life, more stable voltage, and higher capacity. LR626 batteries are alkaline. They have shorter battery life and less stability.

What is SR626SW also known as?

AG4, LR626, 377, or 377A.

What is the shelf life of a SR626SW battery?

Generally 3 to 5 years.

What is the use of SR626SW battery?

Small electronic devices like watches, calculators, remote controls, and medical equipment.

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Anderson Snape

Anderson Snape, born in 1972, completed his undergraduate studies at Loughborough University in the UK in 1993 and received a bachelor's degree in electrical engineering. In 1996, he furthered his studies and obtained a master's degree from Newcastle University. As a senior engineer in the field of integrated circuit testing, Anderson has been working in the chip testing industry for more than 20 years, accumulating profound professional experience and holding unique insights into the industry. He not only focuses on technical practice, but also actively engages in chip-related science popularization work. At the same time, he keeps up with the current hot topics in the semiconductor industry and has made important contributions to the progress and development of the industry.