LR43 Battery: Specifications, Equivalents, and Uses

The LR43 battery is a compact 1.5V alkaline button cell widely used in compact consumer electronics. With a diameter of 11.6 mm and a height of 4.2 mm, this non-rechargeable (primary) coin battery offers stable power for devices that require low to moderate current. Also known as 11.6mm alkaline manganese dioxide 1.5V coin cell, the LR43 remains popular for watches, calculators, laser pointers, and small medical devices.

1. What is LR43 Battery?

2. LR43 Specifications

3. LR43 Batteries Features

4. LR43 Applications

5. LR43 Battery Equivalent

6. LR43 Battery Dimensions

7. LR43 vs LR44 Battery

8. LR43 Manufacturer

9. Frequently Asked Questions about Battery LR43

What is LR43 Battery?

An LR43 battery is a compact, round alkaline button cell designed to supply 1.5 volts of power to small electronic devices. Classified under the IEC code LR43 and often cross-listed as AG12, LR1142, 186, 301, or 386, this battery is part of the popular LR alkaline series commonly used in low- and medium-drain applications. It features a diameter of 11.6 mm and a height of 4.2 mm, making it suitable for devices where requiring  slim and lightweight power sources.

The LR 43 uses alkaline manganese dioxide chemistry, which provides a stable output voltage, good energy density, and low cost. As a primary (non-rechargeable) coin cell, it build for single-use operation and offers a reliable energy supply over a long shelf life of typically 3 to 5 years. This makes it ideal for small medical devices, watches, calculators, remote controls, keychain gadgets, laser pointers, and compact toys.

One of the advantages is LR43’s broad compatibility with other battery codes, enabling users to find replacements easily. While silver-oxide equivalents like SR43 offer higher capacity, the LR 43 remains a widely used, affordable, and accessible option for everyday electronic devices requiring stable 1.5V performance.

LR43 Specifications

LR43 Batteries Features

Consistent 1.5V Output

The battery delivers a stable 1.5V nominal voltage, ensuring that devices requiring steady and predictable power—such as thermometers, watches, calculators, and mini flashlights—operate smoothly without sudden drops in performance.

Slim and Compact Build

With standardized measurements of 11.6 mm in diameter and 4.2 mm in height, the LR 43 engineer for compact electronics. This slim profile allows manufacturers to design smaller, lighter, and more portable devices while still providing sufficient battery power.

Moderate but Reliable Capacity

Offering 110–130 mAh, the battery provides adequate runtime for low- to medium-drain applications. While silver-oxide substitutes offer higher capacities, the battery remains a dependable and affordable solution for products that do not demand high energy consumption.

Long Shelf Stability

Thanks to its alkaline manganese dioxide chemistry, the battery maintains stability even when stored for extended periods. With a typical shelf life of 3 to 5 years, users can keep spare batteries on hand without worrying about rapid self-discharge.

Mercury-Free and Environmentally Safer

Modern LR43 batteries adhere to international safety and environmental regulations. The absence of mercury makes them safer to handle, store, and dispose of compared to older mercury-oxide button cells.

Highly Cost-Effective

One of the primary advantages of the battery is its affordability. It provides a balance of performance and cost, making it a preferred choice for consumer electronics, toys, and mass-produced gadgets.

Wide Compatibility and Interchangeability

The LR43’s size share across many different naming systems.  Interchangeable with multiple types including AG12, LR1142, SR43, 386, 301, and 186, ensuring users can easily find replacements regardless of brand or regional naming conventions.

Lightweight for Portable Devices

Weighing only 1.2–1.5 grams, the LR 43 adds negligible weight to handheld devices, ensuring a comfortable user experience, especially for tools and medical instruments used over long periods.

Safe and Leak-Resistant Construction

High-quality batteries incorporate reinforced seals to minimize leakage risks, protecting devices from damage and increasing overall reliability.

LR43 Applications

Digital Thermometers

One of the most common uses. The slim 4.2 mm height allows it to fit into narrow thermometer compartments while delivering steady voltage for accurate temperature readings.

Laser Pointers and Presentation Tools

Many compact laser pointers rely on LR-43 batteries as their lightweight design and suitable capacity for short bursts of output.

Wristwatches and Small Clocks

Some watch models, especially slim-profile or budget-friendly designs, use LR 43 cells for reliable timekeeping.

Calculators and Pocket Electronics

Basic calculators, mini electronic toys, and portable educational tools frequently use these batteries thanks to their stability and long shelf life.

Medical Devices

Small diagnostic tools such as penlights, glucose meter accessories, and hearing-related gadgets sometimes use LR 43 cells where need moderate runtime and compact size.

Keychain Gadgets

Flashlights, mini alarms, key finders, and novelty items often rely on LR 43 batteries because of their cost-effectiveness and lightweight nature.

Small Remote Controls

Certain car remotes, LED strip remotes, and compact control units use these batteries to maintain a thin form factor.

Electronic Toys and Miniature Gadgets

Lightweight electronic toys, talking devices, and small sound modules can efficiently operate with LR-43 cells as their moderate capacity and safe construction.

Why LR43 Is Effective in These Devices

· Offers stable 1.5V output for predictable performance

· Compact design fits tight battery compartments

· Long shelf life supports devices used occasionally

· Affordable, making it ideal for mass-produced consumer products

· Safe, mercury-free chemistry suitable for sensitive applications

LR43 Battery Equivalent

The LR 43 battery is compatible with several other button cell types across different chemistries, including alkaline, silver-oxide, zinc-air, and older mercury-oxide cells. These equivalents share similar dimensions (11.6 × 4.2 mm) and can function as replacements depending on voltage and performance requirements.

Because LR-43 is an alkaline 1.5V cell, some equivalents offer higher capacity or slightly different discharge characteristics. Choosing the right replacement ensures optimal device performance.

Alkaline Equivalents

· Best for everyday gadgets.

· Slightly lower capacity but cheapest option.

· Common in thermometers, laser pointers, and calculators.

Silver-Oxide

· Offer more stable voltage over the entire discharge cycle.

· Great for medical devices and sensitive electronics.

· Recommended when need long runtime.

Zinc-Air

· Highest capacity but require air to activate.

· Once activated, they cannot reseal.

· Useful only for certain specialized devices.

Mercury-Oxide Equivalents

· Now discontinued as environmental regulations.

· Found in older device documentation.

LR43 Battery Equivalent Chart

Button Battery LR43 Equivalent: SR43, AG12, LR1142, 386, 301, 186

Best direct alkaline equivalents: AG12, LR1142

Best high-performance equivalents: SR43, 386, 301

Highest capacity: 186 (zinc-air)

All share the same physical size: 11.6 mm (diameter) × 4.2 mm (height)

LR43 Battery Dimensions

The battery follows the standard dimensions of the LR1142 button cell format. Its compact size allows it to fit into slim, lightweight electronic devices where space is limited.

Physical Dimensions of the Battery

· Diameter: 11.6 mm

· Height (Thickness): 4.2 mm

· Shape: Round, flat button/coin cell

· Standard Size Code: 1142 (11.6 mm × 4.2 mm)

The batteries design to be a low-profile button cell, making it ideal for devices that require a thinner battery compartment. With a diameter of 11.6 mm, it offers a stable footprint for device contacts while keeping its height at just 4.2 mm to maintain a compact form. This size strikes a balance between portability and capacity, allowing the battery to provide adequate energy without increasing device thickness.

Its small, coin-like shape makes it particularly useful in electronics where weight and space are critical factors, such as digital thermometers, keychain tools, miniature toys, laser pointers, and small medical devices. Although compact, the 1142 size standard share among several equivalent battery models (e.g., AG12, SR43, 386), making replacements widely available across markets.

LR43 vs LR44 Battery

Although both the batteries appear similar at first glance, they differ in size, capacity, and suitability for various devices. Understanding these differences is necessary to avoid incorrect replacements and ensure optimal device performance.

Impacts on Device Performance

LR43: Compact size and moderate capacity make it ideal for small, low-drain devices.

LR44: Higher capacity ensures longer runtime, especially in devices with medium power demands.

Using LR44 in place of LR 43 not physically fit as its extra height. Conversely, using LR43 in a device designed for LR44 reduce operating time.

Applications and Suitability

LR43 Applications: Thermometers, small laser pointers, wristwatches, calculators, keychain gadgets.

LR44 Applications: Cameras, calculators, toys, meters, small electronics requiring longer runtime or higher current.

Observation: Devices specifically designed for LR 43 often cannot accommodate the taller LR44, even though electrical compatibility exists.

Observations from Usage

Many users assume interchangeability as identical diameter, but height and capacity differences are critical.

LR44 provides more energy but damage compartments not designed for extra thickness.

LR43 remains the preferred choice for ultra-compact electronics, while LR44 is suitable when need longer operation or higher energy output.

Always recommend checking device manual or markings before replacement.

LR43 Manufacturer

Several reputable manufacturers produce these batteries, ensuring quality, reliability, and global availability. These brands know for their consistent performance, long shelf life, and adherence to international safety standards. Below are some of the most trusted LR 43 battery manufacturers:

Murata LR43 Button Battery

Murata produces high-quality batteries with stable 1.5V output and long-lasting performance. Their batteries know for leak-resistant construction and reliability in small electronics such as digital thermometers, watches, calculators, and keychain gadgets. Murata emphasizes durability, making their batteries a preferred choice for both consumer and professional devices.

Maxell LR43 Battery

Maxell offers batteries that combine consistent energy output with safety and environmental compliance. Their mercury-free design ensures safe handling and disposal. Maxell LR-43 cells commonly use in precision electronics, low- to medium-drain devices, and portable gadgets, making them ideal for applications where reliable performance is essential. 

Toshiba LR43 Battery

Toshiba’s batteries design for long shelf life and dependable voltage stability. Widely use in medical devices, small toys, calculators, laser pointers, and watches, Toshiba batteries provide reliable performance in devices requiring precise power. The brand’s commitment to quality ensures minimal leakage and consistent energy delivery over time.

Duracell LR43 Battery

Duracell batteries recognize for high reliability and global availability. With a long shelf life and stable 1.5V output, they widely use in consumer electronics such as thermometers, wristwatches, calculators, and keychain gadgets. Duracell emphasizes safety, performance consistency, and dependable energy supply for low- to medium-drain applications.

Frequently Asked Questions about Battery LR43

What does LR stand for when it comes to batteries?

“LR” indicates alkaline manganese dioxide chemistry in a round button cell. The “L” refers to alkaline, which provides stable voltage and long shelf life, while “R” refers to the round shape. LR batteries are non-rechargeable (primary) and commonly used in small electronics such as watches, calculators, and compact medical devices as their reliability and low cost.

Are LR43 and LR44 batteries interchangeable?

No, LR43 and LR44 batteries are not fully interchangeable. While both provide 1.5V and share the same diameter (11.6 mm), LR44 is taller (5.4 mm vs 4.2 mm) and has higher capacity. Using LR44 in an LR43 compartment not fit, while using LR 43 in an LR44 device reduces runtime and affect performance.

Is LR43 the same as 386?

Yes, 386 is a silver-oxide equivalent of the LR 43 battery. While LR43 is alkaline, 386 offers higher capacity (150–180 mAh) and more stable voltage over time. Both share the same diameter and height, making 386 a suitable replacement for devices needing longer life or consistent voltage.

Is LR43 the same as AG12?

Yes, AG12 is another name for the LR 43 battery. Both are alkaline 1.5V coin cells with dimensions 11.6 × 4.2 mm. AG12 use interchangeably with LR 43 in many devices. Other equivalent codes include LR1142, 386, 301, and SR43 (silver-oxide), allowing easy replacements worldwide.

What are LR43 Batteries Used For?

LR43 batteries power small, low- to medium-drain devices, including digital thermometers, laser pointers, calculators, wristwatches, keychain gadgets, toys, and small medical tools. Their compact size, stable 1.5V output, and lightweight design make them ideal for devices where space is limited but consistent energy is essential.

What Battery Can Replace LR43?

Common replacements include AG12, LR1142, SR43, 386, 301, and 186. Alkaline equivalents (AG12, LR1142) match voltage and size, while silver-oxide replacements (SR43, 386, 301) offer longer life and more stable voltage. Zinc-air 186 cells are also compatible in some specialized low-drain devices. Always check device compatibility before replacement.

What is the difference between LR43 and LR44 batteries?

Both are 1.5V alkaline coin cells with the same diameter, but LR44 is taller (5.4 mm vs 4.2 mm) and has higher capacity (150–180 mAh vs 110–130 mAh). LR44 provides longer runtime, but it not physically fit in devices designed for LR 43, which prefer for compact, slim devices.

How Long do LR43 Batteries Last?

LR43 batteries have a shelf life of 3–5 years. In devices, their lifespan depends on usage and power demand, typically 6 months to 2 years in low- to medium-drain electronics. Using this battery in high-drain devices reduces operational time, so device type and frequency of use impact battery longevity.

What battery is equivalent to LR43?

Equivalent batteries include AG12, LR1142, SR43, 386, 301, and 186. Alkaline equivalents match voltage and size, silver-oxide equivalents offer higher capacity and more stable voltage, and zinc-air equivalents provide high capacity for specialized devices. Mercury-oxide MR43 is obsolete and no longer recommended.

Where can I buy LR43 batteries?

These batteries are widely available online and in stores. Options include Amazon, eBay, electronics retailers, battery specialty shops, and local hardware stores. Popular brands like Duracell, Maxell, Toshiba, and Murata offer reliable batteries. Check packaging for compatible codes (AG12, LR1142, SR43) to ensure proper replacement.

Conclusion

The LR43 battery is a reliable, 1.5V alkaline coin cell widely use in thermometers, watches, calculators, laser pointers, and small electronic gadgets. Its long shelf life, stable voltage, and compact 11.6 × 4.2 mm size make it an ideal choice for low- to medium-drain devices.

For replacement, the LR 43 is compatible with equivalents such as AG12, LR1142, SR43, 386, 301, and 186, providing options for both everyday use and higher-performance needs. Understanding the difference between LR43 and LR44 batteries ensures proper device performance and avoids fitment issues.

Whether you need a cost-effective LR 43 battery replacement or a high-capacity silver-oxide equivalent, choosing the right battery guarantees optimal device performance and longer runtime. With widespread availability from trusted brands like Duracell, Maxell, Toshiba, and Murata, LR43 remains a versatile and dependable power solution for small electronics.

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