ER26500 Battery Guide: Specifications, Applications and Industrial IoT Solutions
The ER26500 battery is a C-size, 3.6V lithium thionyl chloride primary cell developed for long-term industrial applications. Its combination of stored energy, low self-discharge and compact dimensions makes it relevant to smart meters, remote sensors, asset tracking and other devices with limited access to charging or maintenance.
Selecting an ER26500 requires more than checking capacity. Engineers must distinguish between the standard bobbin-type ER26500, the higher-power ER26500M and an ER26500 battery pack combined with a hybrid pulse capacitor.
This guide explains the verified specifications of PKCELL’s standard ER26500, compares ER26500 with ER26500M and shows how each architecture can support Industrial IoT applications.
Quick Answer: When Should You Use an ER26500 Battery?
Consider ER26500 when a device requires a 3.6V primary battery, has a low or moderate average load, must operate for an extended period and cannot be recharged easily.
Standard ER26500: Best starting point for long-term energy and low continuous current.
ER26500M: Consider when the application requires stronger direct current delivery.
ER26500 + HPC: Consider for NB-IoT, LoRaWAN or cellular devices with short transmission pulses.
Custom ER26500 pack: Use when the OEM needs multiple cells, connectors, wires, sealing or a specific mechanical configuration.
PKCELL ER26500 Battery Specifications
The following values are based on the PKCELL ER26500 8500mAh technical specification. Capacity is measured under the datasheet’s specified discharge conditions and should not be treated as fully usable capacity in every device.
| Parameter | PKCELL ER26500 Reference Value | Engineering Note |
|---|---|---|
| Chemistry | Lithium thionyl chloride, LiSOCl2 | Primary, non-rechargeable chemistry |
| Physical format | C size | Confirm the pack and terminal dimensions |
| Rated voltage | 3.6V | Verify the complete device operating range |
| Nominal capacity | 8500mAh | Measured at 3mA to a 2.0V endpoint at 23 ± 2°C |
| Maximum continuous discharge | 130mA | Not a recommended continuous design current |
| Maximum pulse discharge | 300mA | Pulse conditions and voltage response must be tested |
| Operating temperature | -55°C to +85°C | Available capacity and pulse voltage vary with temperature |
| Approximate dimensions | 26.2 × 50.5mm | Allow additional room for tabs, wires and insulation |
| Approximate weight | 55g | A complete battery pack will weigh more |
| Storage self-discharge | Up to approximately 1% per year under specified conditions | Depends on storage temperature and duration |
| Reference storage life | 10 years at room temperature | Storage life is not the same as device operating life |
| Termination options | Standard, solder tabs and axial pins | Custom wires and connectors may also be available |
Download the PKCELL ER26500 8500mAh datasheet
ER26500 vs ER26500M vs ER26500 with HPC
These three options share a C-size format and 3.6V platform but address different load requirements.
| Feature | Standard ER26500 | ER26500M | ER26500 + HPC |
|---|---|---|---|
| Primary design objective | Maximum stored energy for low-rate discharge | Stronger direct current and pulse capability | Long-term energy plus short pulse support |
| Representative capacity | 8500mAh for the referenced datasheet | 6500mAh for the referenced product | Depends on cell count and pack configuration |
| Continuous current | Up to 130mA for the referenced model | Up to 1000mA for the referenced current product | Baseline load supplied by the ER cell |
| Pulse current | Up to 300mA for the referenced model | Up to 2000mA for the referenced current product | HPC supports short pulse events |
| Typical load pattern | Low continuous current and infrequent events | Higher direct current or stronger pulses | Long sleep periods plus wireless bursts |
| Potential applications | Meters, data loggers and low-power sensors | Tracking, alarms, actuators and higher-power sensors | NB-IoT, LTE-M, LoRaWAN and smart metering |
| Main tradeoff | Limited pulse performance compared with power type | Lower nominal capacity than standard type | Additional space, components and pack engineering |
Current limits vary among product versions and datasheet revisions. Use the document issued for the exact model being purchased.
ER26500 Battery Applications
Utility IoT
Smart Water, Gas and Heat Meters
Smart meters combine long sleep periods with scheduled readings, alarms and wireless transmissions. The standard ER26500 can supply long-term energy, while an HPC may support stronger communication pulses.
Selection data: Sleep current, transmissions per day, network retries, cutoff voltage and temperature.
Industrial sensing
Pressure and Flow Monitoring
Remote pressure gauges and flow sensors may operate in pipelines, water-treatment systems and industrial plants where regular battery replacement is disruptive.
Selection data: Sampling interval, display load, transmitter current and environmental requirements.
Smart city
Manhole and Parking Sensors
Underground infrastructure sensors may monitor cover movement, water level, parking occupancy or unauthorized access while communicating through LPWAN networks.
Selection data: LoRaWAN or NB-IoT pulses, moisture protection, storage time and service access.
Remote assets
GPS and Asset Tracking
Trackers may remain asleep before waking for GNSS acquisition and data transmission. A standard ER26500, ER26500M or ER + HPC solution may be evaluated according to the pulse profile.
Selection data: GNSS acquisition time, reporting frequency, signal conditions and enclosure size.
Automation
Smart Valves and Actuators
Motorized valves can create current demands beyond those of the sensing electronics. The actuator load must be evaluated separately from the radio load.
Selection data: Startup current, movement duration, operating frequency and minimum motor voltage.
Remote monitoring
Industrial Data Loggers
Data loggers and environmental monitors can use the ER26500 when they need long-term power for measurement, memory and periodic uploads without a dependable charging source.
Selection data: Sensor warm-up time, logging interval, storage load and data-upload schedule.
Safety systems
Wireless Alarms and Detectors
Security and safety devices may spend most of their time in standby but must wake reliably for testing, alarm reporting or status transmission.
Selection data: Standby current, alarm duration, siren or radio load and required replacement interval.
Agricultural IoT
Irrigation and Field Sensors
Soil, water-level and irrigation sensors may be deployed far from mains power and exposed to seasonal temperature changes.
Selection data: Sensor duty cycle, communication range, enclosure sealing and solar availability.
ER26500 Industrial IoT Power Solutions
The correct solution depends on the relationship between the device’s average energy consumption and its short-term power demand.
Solution 1: Single Standard ER26500
Use a standard bobbin-type ER26500 when the device has low continuous current and any pulses remain within the cell’s verified limits.
Potential fit: Basic AMR meters, memory backup, low-power data loggers and infrequently transmitting sensors.
Solution 2: ER26500M Power Type
Consider ER26500M when the application needs stronger current delivery directly from the cell and accepts a lower nominal capacity.
Potential fit: Tracking devices, alarms, actuators and sensors with more demanding load events.
Solution 3: ER26500 + HPC
Pair a standard ER26500 with a hybrid pulse capacitor when the device combines long sleep periods with short NB-IoT, LTE-M or LoRaWAN transmission pulses.
Potential fit: Smart meters, cellular sensors, smart manhole covers and infrastructure trackers.
Solution 4: Multi-Cell Battery Pack
Connect cells in series or parallel only through an engineered pack design that accounts for cell matching, insulation, protection and assembly consistency.
Potential fit: Devices requiring higher voltage, more capacity or a specific service-life target.
How ER26500 + HPC Works
- During sleep: The ER26500 supplies the low baseline current and restores energy to the pulse-support component.
- During transmission: The HPC supports the short higher-current event.
- During recovery: The ER cell gradually replenishes the HPC before the next pulse.
- At system level: The design aims to keep voltage above the device cutoff threshold.
A larger capacitor does not automatically solve an IoT pulse problem. Engineers must evaluate capacitance, ESR, pulse duration, voltage margin, recharge interval and low-temperature behavior.
How to Estimate ER26500 Battery Life
Do not assign a fixed 8-, 10- or 15-year operating life to every ER26500 application. Calculate continuous and intermittent consumption separately.
Continuous Consumption
Event Consumption
Initial Runtime Estimate
The result must then be adjusted for:
- Storage time before activation
- Self-discharge
- Operating temperature
- Passivation and voltage delay
- Communication retries
- Pulse losses
- Device cutoff voltage
- Component and usage variation
- Required engineering margin
ER26500 Selection Checklist
- Measure sleep current. Include every circuit that remains active between events.
- Capture the largest pulse. Measure current, duration and minimum voltage.
- Record the communication profile. Include scheduled transmissions, retries and alarms.
- Check device cutoff voltage. Capacity below the cutoff voltage is unavailable to the device.
- Define the environment. Include operating temperature, storage temperature, humidity and vibration.
- Select the architecture. Compare standard ER26500, ER26500M and ER26500 + HPC.
- Define mechanical requirements. Specify tabs, pins, wires, connectors, insulation and sealing.
- Run a life calculation. Use measured rather than assumed current values.
- Test the complete product. Validate fresh, stored, cold and representative end-of-life conditions.
Common ER26500 Design Mistakes
- Mixing ER26500 and ER26500M parameters: The standard and power versions have different capacity and current characteristics.
- Treating maximum current as a recommended load: Maximum ratings are not necessarily appropriate for continuous product design.
- Selecting by capacity only: A battery may retain energy but fail to maintain voltage during a pulse.
- Ignoring passivation: Storage history can affect initial voltage response.
- Claiming waterproof performance from the cell: The complete pack and device enclosure determine environmental protection.
- Promising a fixed service life: Runtime depends on load, temperature, cutoff voltage and network behavior.
- Recharging ER26500: ER26500 is a primary battery and must not be charged.
Need an ER26500 Battery for an Industrial IoT Project?
Send PKCELL your voltage range, sleep current, pulse current, pulse duration, communication method, temperature range, target lifetime and mechanical requirements. The engineering team can evaluate standard ER26500, ER26500M or ER26500 + HPC.
Request an ER26500 Recommendation
View ER + HPC Battery Packs
Frequently Asked Questions
What is the capacity of an ER26500 battery?
The referenced PKCELL ER26500 datasheet specifies 8500mAh when discharged at 3mA to 2.0V at 23 ± 2°C. Other ER26500 versions may list different capacities, so verify the exact datasheet.
What is the difference between ER26500 and ER26500M?
Standard ER26500 prioritizes stored energy for lower-rate discharge. ER26500M is a power-type version with lower nominal capacity but stronger continuous and pulse-current capability.
Can ER26500 power an NB-IoT device?
It can be part of an NB-IoT power system, but the communication pulse must be evaluated. An ER26500 with HPC or an ER26500M may be required depending on current, duration and cutoff voltage.
How long does an ER26500 last?
There is no universal operating life. Runtime depends on usable capacity, continuous current, pulse consumption, transmission frequency, storage time, temperature and device cutoff voltage.
Can an ER26500 battery be recharged?
No. ER26500 is a primary lithium thionyl chloride battery and must not be recharged.
When should I use ER26500 with an HPC?
Consider ER26500 with HPC when an IoT device has low average consumption but produces short higher-current events during NB-IoT, LTE-M, LoRaWAN, GNSS or actuator operation.
Conclusion
The ER26500 is a strong option for long-term Industrial IoT devices that need a 3.6V primary power source and have limited access to maintenance or charging.
Standard ER26500 is optimized for stored energy, ER26500M addresses stronger direct current requirements, and ER26500 with HPC combines long-term energy with short pulse support.
Final selection should be based on measured load data, the exact model datasheet, battery-life calculations and testing in the complete device.
Sources and Verification Notes
Product specifications can change. Use the datasheet supplied for the exact production model as the final technical reference.
- PKCELL ER26500 8500mAh Datasheet — voltage, capacity, current, temperature and storage specifications.
- PKCELL ER26500M Product Page — power-type ER26500M reference information.
- PKCELL ER + HPC Solutions — pulse-support battery pack products.
- ER26500 + HPC for Smart Meters — metering power architecture.
- ER26500 for Pressure Monitoring — industrial gauge application.
- ER26500 for Smart Manhole Covers — smart-city application.
- ER26500 for Smart Valves — industrial automation application.
Post time: Aug-25-2025
