HRM-10 Battery Voltage Internal Resistance Tester

The HRM-10 Battery Voltage Internal Resistance Tester is a compact handheld precision instrument designed for measuring battery voltage and internal resistance. It is ideal for evaluating battery condition, comparing cells, sorting battery batches and detecting aged or degraded batteries that may still show normal voltage but have increased internal resistance.

The HRM-10 measures voltage and internal resistance simultaneously, helping users quickly assess battery health and performance. Internal resistance is an important indicator of battery condition, as a higher resistance may indicate ageing, reduced discharge capability, lower efficiency or potential failure.

🔧 Key Features

• 🔋 Simultaneous battery voltage and internal resistance measurement
• 🎯 True 4-wire Kelvin measurement method
• 📊 TFT HD color display for clear measurement readings
• ⚙️ Automatic and manual range selection
• ✅ Battery sorting mode with user-defined thresholds
• 🧾 Historical measurement records
• 💾 Measurement data export support
• 🔌 USB Type-C rechargeable design
• 🧪 Suitable for lithium, lead-acid, alkaline, household, automotive and other battery types

📐 Technical Specifications

Parameter	Specification
Brand	FNIRSI
Model	HRM-10
Product type	Battery voltage and internal resistance tester
Voltage measuring range	0 ~ ±100 V DC
Voltage ranges	Auto, 1 V, 10 V, 100 V
Resistance measuring range	0 ~ 200 Ω
Resistance ranges	Auto, 20 mΩ, 200 mΩ, 2 Ω, 20 Ω, 200 Ω
Accuracy	±0.5%
Signal frequency	AC 1 kHz
Measurement method	4-wire Kelvin measurement
User calibration	Supported
Sorting mode	Supported
Sorting groups	8 user-defined threshold groups
History records	Supported
Data export	Supported
Power supply	Built-in rechargeable lithium battery
Battery	3.7 V / 1000 mAh
Charging interface	USB Type-C, 5 V / 1 A
Working environment	-10 °C ~ +45 °C, relative humidity < 80%
Storage environment	-20 °C ~ +80 °C, relative humidity < 80%
Dimensions	158.7 × 80.5 × 28.4 mm
Weight	approx. 225 g

⚡ Advantage of 4-Wire Kelvin Measurement

The HRM-10 uses a 4-wire Kelvin measurement method, which improves accuracy when measuring very low resistance values. In standard low-resistance measurements, test lead resistance, contact resistance and clip resistance can affect the result. The Kelvin method helps reduce these errors, allowing the internal resistance of the battery to be measured more accurately.

This is especially useful for testing:

• 18650, 21700 and other lithium-ion cells
• LiFePO4 batteries
• Lead-acid batteries
• NiMH / NiCd cells
• AA, AAA and other household batteries
• Battery packs and assembled battery modules

✅ Battery Sorting Mode

The HRM-10 includes a convenient sorting mode. Users can set voltage and resistance threshold values, allowing the tester to classify batteries based on predefined criteria. This function is especially helpful when testing larger quantities of cells and selecting batteries with similar performance characteristics.

The device supports up to 8 threshold groups, making it suitable for different battery types and sorting standards.

🧾 History and Data Export

The HRM-10 supports historical measurement records and data export. This makes it easier to track battery condition over time, document test results and use the data for maintenance, quality control or technical analysis.

📦 Package Contents

• HRM-10 tester – 1 pc
• Clip test leads – 1 set
• USB Type-C data / charging cable – 1 pc
• User manual – 1 pc
• Packaging box – 1 pc

⚠️ Usage Notes

• The device is intended for DC voltage measurement only.
• Do not apply DC voltage higher than 100 V.
• Do not apply AC voltage under any circumstances.
• For best results, use clean and firm contact points.
• Store the tester in a dry and clean place, protected from moisture, impact and direct sunlight.

🎯 Applications

The HRM-10 is suitable for electronics workshops, battery diagnostics, service work, battery pack assembly, maintenance, solar energy systems, RC models, power tools, automotive batteries and other battery-powered systems.