ER34615 3.6V 19Ah Li-SOCl2 Battery for Smart Meters & IoT

ER34615 3.6V 19Ah Li-SOCl2 Battery: A Long-Life Power Solution for Smart Meters, IoT and Industrial Devices

For many industrial and IoT applications, battery replacement is not simply inconvenient—it can be expensive, difficult, or even impossible once a device has been deployed in the field.

Smart utility meters, remote monitoring equipment, wireless sensors, security systems, data loggers, tracking devices, and industrial instruments may need to operate for many years with minimal maintenance. In these applications, the battery must provide stable voltage, very low self-discharge, high energy density, and reliable operation across a wide temperature range.

This is exactly where the ER34615 3.6V 19Ah Li-SOCl2 battery becomes an attractive power solution.

The ER34615 is a D-size lithium thionyl chloride (Li-SOCl₂) primary battery designed for applications where long operating life and high energy capacity are more important than rechargeability.

At Cowon, we supply ER-series primary lithium cells as well as customized battery assemblies for industrial, IoT, metering, security, and remote monitoring applications.

You can explore our complete range of Li-SOCl2 batteries for additional cell sizes and configurations.

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What Is an ER34615 Battery?

The ER34615 is a cylindrical lithium thionyl chloride primary battery with a nominal voltage of 3.6V.

A typical high-capacity ER34615 cell can provide approximately 19Ah / 19,000mAh, making it one of the higher-capacity cylindrical primary lithium cells used in industrial applications.

Typical characteristics include:

Specification	Typical ER34615
Battery Chemistry	Lithium Thionyl Chloride (Li-SOCl₂)
Nominal Voltage	3.6V
Typical Capacity	Up to 19Ah / 19,000mAh
Cell Size	D Size
Rechargeable	No
Self-Discharge	Very low
Application Type	Long-life industrial and IoT equipment
Available Configuration	Single cell or customized battery pack

Because specifications such as dimensions, discharge current, pulse capability, terminals, and operating temperature can vary between standard ER34615 and high-rate ER34615M versions, engineers should always confirm the exact datasheet before finalizing a design.

For a typical 19Ah option, see our ER34615 3.6V 19Ah Li-SOCl2 battery.

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Why Is the ER34615 Popular for Long-Life Industrial Devices?

The biggest advantage of the ER34615 is not simply its 19Ah capacity.

Its Li-SOCl₂ chemistry is particularly suitable for devices designed to remain in service for many years.

1. High Energy Capacity in a Compact Cylindrical Cell

With capacity reaching approximately 19Ah, the ER34615 stores a significant amount of energy in a D-size cylindrical format.

This makes it useful for devices where:

• battery replacement intervals must be extended;

• available installation space is limited;

• the equipment consumes relatively low average current;

• long standby periods are required;

• maintenance costs are high.

Instead of designing around multiple smaller cells, engineers may be able to use one ER34615 or a customized multi-cell battery configuration.

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2. Extremely Low Self-Discharge

One of the defining characteristics of lithium thionyl chloride chemistry is its very low self-discharge.

For remote devices that may remain installed for years, this is extremely important.

A conventional battery can lose a meaningful amount of stored energy simply while sitting unused. Li-SOCl₂ batteries, by comparison, are designed to preserve their stored capacity for much longer periods.

That makes ER34615 batteries particularly suitable for applications that spend most of their time in standby mode and only periodically wake up to measure, record, or transmit data.

Typical examples include:

• smart water meters;

• smart gas meters;

• electricity meters;

• remote IoT sensors;

• alarm systems;

• GPS tracking devices;

• environmental monitoring equipment.

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3. Stable 3.6V Operating Voltage

The ER34615 provides a nominal voltage of 3.6V, which is well suited to many low-power electronic circuits.

A relatively stable discharge voltage can simplify system design and help electronic equipment operate consistently over an extended service period.

This is particularly valuable for industrial equipment that must maintain predictable performance over several years.

Depending on the electronic design, one cell may be sufficient, while multiple cells can also be connected in series or parallel to achieve different voltage or capacity requirements.

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4. Suitable for Wide-Temperature Environments

Remote monitoring and industrial devices are often installed outside climate-controlled environments.

A utility meter may be mounted outdoors. A sensor may be deployed inside a remote cabinet. A tracking system may experience both high summer temperatures and cold winter conditions.

Li-SOCl₂ chemistry is widely selected for these environments because suitable cells can operate across a broad temperature range.

Cowon's current ER-series products include versions specified for operation in demanding temperature environments. However, the exact operating range should always be confirmed for the selected model and expected discharge current.

Temperature affects not only battery capacity but also voltage behavior and pulse performance, so engineers should evaluate the complete load profile instead of selecting a battery based only on nominal capacity.

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Typical Applications of ER34615 3.6V 19Ah Batteries

Because of its combination of high capacity, low self-discharge, and long-term reliability, the ER34615 can be used across a wide variety of industrial applications.

Smart Electricity, Gas and Water Meters

Smart metering is one of the most common applications for ER-series Li-SOCl₂ batteries.

An electricity, gas, or water meter may need to remain operational for many years without frequent maintenance.

The battery may need to power:

• measurement circuits;

• memory backup;

• LCD displays;

• wireless communication modules;

• valves or actuators;

• periodic data transmission.

For these applications, battery life is often a major part of the total system design.

Cowon also offers high-draw ER34615M battery solutions for electricity, gas and water meters.

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IoT Sensors and Remote Monitoring Systems

Many IoT devices operate according to a similar pattern:

Sleep → Wake Up → Measure → Transmit → Return to Sleep

Average current consumption may be extremely low, but wireless communication can create a short current pulse.

This makes battery selection more complicated than simply comparing Ah capacity.

ER34615 batteries can be used in applications such as:

• environmental sensors;

• temperature monitoring;

• pipeline monitoring;

• agricultural sensors;

• smart infrastructure;

• remote equipment monitoring;

• industrial wireless nodes.

For a successful design, both the average current and peak pulse current should be evaluated.

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Industrial Data Loggers

Data loggers are frequently installed in locations where technicians cannot easily replace batteries.

Applications may include:

• factory monitoring;

• oil and gas equipment;

• environmental monitoring;

• transportation systems;

• remote machinery;

• utility infrastructure.

A high-capacity primary battery can help extend maintenance intervals and reduce the overall cost of servicing the equipment.

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Wireless Security and Alarm Systems

Wireless alarm systems, security sensors, access-control devices, and remote detectors often remain in standby mode for long periods.

These applications benefit from:

• low self-discharge;

• stable voltage;

• long storage life;

• reliable standby operation;

• compact battery dimensions.

The ER34615 can therefore be considered for security products requiring long-term autonomous operation.

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GPS and Asset Tracking Equipment

Asset tracking devices may be installed on containers, industrial equipment, vehicles, or other valuable assets.

Depending on reporting frequency, a tracking device can remain in standby for long periods and periodically activate its GPS and communication module.

Battery life can therefore be extended significantly when the cell is properly matched to the transmission frequency and peak current requirements.

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ER34615 vs. ER26500: Which Battery Should You Choose?

ER34615 and ER26500 both belong to the Li-SOCl₂ primary lithium battery family, but they target different capacity and size requirements.

A typical comparison is:

Feature	ER26500	ER34615
Nominal Voltage	3.6V	3.6V
Chemistry	Li-SOCl₂	Li-SOCl₂
Typical Capacity	Around 8.5–9Ah	Up to around 19Ah
Relative Size	Smaller	Larger D-size cell
Energy Capacity	Medium	High
Typical Use	Compact industrial devices	Long-life, higher-energy industrial devices

If equipment has enough installation space and requires significantly longer operating life, the ER34615 19Ah is often the stronger candidate.

If physical size is more important and the required energy consumption is lower, an ER26500 may be more appropriate.

For comparison, you can view our ER26500 3.6V 9Ah Li-SOCl2 battery.

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ER34615 vs. ER34615M: Pay Attention to Pulse Current

This is one of the most important factors when selecting an ER34615 battery.

Not every 19Ah ER34615 cell has the same discharge capability.

A standard energy-type ER34615 is generally optimized for high capacity and long-duration low-current discharge.

An ER34615M or high-rate version, depending on cell construction, can be designed to provide significantly higher continuous or pulse current.

This matters when the device contains components such as:

• GSM modules;

• NB-IoT modules;

• LoRa transmitters;

• LTE communication modules;

• motors;

• valves;

• actuators;

• high-power RF transmitters.

A battery might have enough total capacity to power the device for years but still fail to provide sufficient voltage during a short high-current transmission pulse.

Therefore, when selecting the battery, do not evaluate only:

“How many Ah does the battery have?”

Also ask:

“What continuous current and peak pulse current does my equipment require?”

For some low-power IoT devices, a standard high-energy ER34615 may be appropriate.

For applications with stronger current pulses, an ER34615M, a different internal construction, or an ER battery combined with a suitable pulse-support solution may be required.

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Battery Passivation: What Engineers Should Know

Lithium thionyl chloride batteries can develop a thin passivation layer on the lithium anode during storage.

This phenomenon helps reduce self-discharge and is one reason Li-SOCl₂ batteries can achieve such long storage and standby life.

However, after extended storage, passivation can also temporarily cause voltage delay when a load is first applied.

The actual effect depends on factors including:

• storage time;

• storage temperature;

• cell design;

• discharge current;

• operating temperature;

• previous discharge history.

For equipment with strict voltage requirements or high startup current, engineers should evaluate passivation behavior during prototype testing.

This is another reason why choosing an industrial battery should involve more than simply comparing voltage and capacity.

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How to Select the Right ER34615 Battery

Before purchasing an ER34615 battery for a new project, provide your battery supplier with as much information as possible.

The most useful parameters include:

Required Voltage

Is the device designed for 3.6V, 7.2V, 10.8V, or another voltage?

Multiple ER34615 cells can be configured when a higher battery-pack voltage is required.

Required Capacity

How long should the equipment operate before battery replacement?

A 19Ah cell may provide long service life, but actual runtime depends heavily on the device's current consumption and operating pattern.

Average Current

Provide the normal operating current and sleep current.

Maximum Pulse Current

This is particularly important for wireless communication, actuators, and motorized devices.

Pulse Duration and Frequency

For example, a device drawing a large pulse for one second every hour behaves very differently from one drawing the same current continuously.

Operating Temperature

Tell the battery supplier the lowest and highest temperatures expected in the actual application.

Required Terminal or Connector

ER34615 cells can be supplied with different connection methods depending on the project, such as:

• tabs;

• leads;

• connectors;

• battery holders;

• custom wiring;

• customized battery packs.

Installation Space

Provide the available battery compartment dimensions, especially when replacing an existing battery.

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Customized ER34615 Battery Packs

Some projects require more than a standard bare cell.

Depending on the application, ER34615 cells can be assembled into customized configurations to achieve different voltage and capacity requirements.

For example:

• 1S2P: increased capacity while retaining approximately 3.6V;

• 1S3P: further increased capacity at approximately 3.6V;

• 2S: approximately 7.2V nominal voltage;

• 3S: approximately 10.8V nominal voltage.

Customized assemblies can also incorporate appropriate leads, connectors, insulation, packaging, and other project-specific components.

For example, Cowon currently offers an ER34615 1S3P 3.6V 57Ah battery configuration for projects requiring substantially higher capacity.

The exact battery configuration should always be designed according to the equipment's electrical load, installation environment, and safety requirements.

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Why Work With Cowon for ER34615 Battery Projects?

Battery selection becomes especially important for industrial products intended to operate for many years.

Founded in 2008, Cowon focuses on battery cells, replacement batteries, and customized battery solutions for a wide range of electronic and industrial equipment.

Our battery portfolio includes:

• Li-SOCl₂ primary batteries;

• lithium-ion cylindrical cells;

• lithium-polymer batteries;

• LiFePO4 batteries;

• Li-MnO₂ primary batteries;

• Ni-MH batteries;

• customized battery packs.

You can learn more about our manufacturing and battery development capabilities on the Cowon About Us page.

For ER34615 projects, our team can help evaluate requirements including cell capacity, discharge characteristics, pack configuration, terminals, wiring, connectors, and application conditions.

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Conclusion

The ER34615 3.6V 19Ah Li-SOCl₂ battery is an excellent choice for equipment that requires high energy capacity, extremely low self-discharge, stable long-term performance, and extended maintenance intervals.

It is particularly suitable for:

• smart electricity meters;

• gas meters;

• water meters;

• IoT sensors;

• industrial data loggers;

• wireless monitoring equipment;

• security devices;

• GPS and asset tracking systems;

• remote industrial instruments.

However, selecting the correct ER34615 requires more than checking voltage and capacity.

Engineers should also evaluate continuous current, pulse current, operating temperature, passivation, installation space, communication frequency, and expected service life.

If your device requires a standard ER34615 19Ah cell, a higher-pulse ER34615M, or a customized multi-cell battery pack, Cowon can help evaluate the appropriate configuration for your application.

Contact Cowon with your required voltage, capacity, maximum current, operating temperature, dimensions, connector, and estimated order quantity to discuss your ER34615 battery project.