10 Best 18650 Battery Internal Resistance Tester of 2025

Tested and Reviewed: Top 10 18650 Battery Internal Resistance Tester deals with expert ratings from 8.1 to a perfect 10

February 2026 Edition

Editor's Choice

9.7

FNIRSI

FNIRSI HRM-10 Voltage Internal Resistance Battery Tester，Battery Voltage Meter for Types of Batteries, Car Battery Tester, AAA AA Battery, 100V 200Ω, Digital Battery Analyzer for Household Automotive

Free Shipping

Editor's bottom line:

“This 18650 battery internal resistance tester is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

Voltage Internal Resistance Battery TesterFNIRSI battery tester can automatically test internal resistance and voltage value at the same time. The measured value can be used to determine whether the battery quality has decreased
TFT HD Color DisplayThe display adopts advanced color HD technology and excellent layout. Compared with traditional monochrome displays, it can present test results more clearly and vividly, greatly enhancing the user's measurement experience
Accurate MeasurementAdopts customized Kelvin four-wire connection method to avoid wire and contact resistance and improve measurement accuracy. Users can also manually adjust the voltage and resistance range
Wide Application RangeSuitable for all kinds of batteries. Car battery tester, household battery. It supports historical records and export data tables of historical measurements. View 8 sets of voltage and resistance values to batch select batteries
LED Display Handheld MeterThe resistance measurement range is up to 200 and the voltage measurement range is up to 100 V. The device must not be used with a DC voltage higher than 100V. Do not apply AC voltage under any circumstances

Show Price

Picked by 397 people today

9.5

DWEII

DWEII 1pcs 18650 Lithium Battery Capacity Tester Module MAh MWh Digital Battery Power Detector Module 18650 Tester Type-C (4 Channel)

Free Shipping

Main Highlights

1pcs 18650 Battery Capacity Tester LCD Display Digital Automatic Charge and Discharge Internal Resistance Tester MAh MWh Lithium Battery Type-C Port Tester
Supports four-channel capacity and internal resistance measurement.(User manual available if do as follow: click "DWEII"(you can find "Sold by DWEII" under Buy Now button), in the new page, click "Ask a question".)we will send you the manual asap
Measurement parameters: Working voltage: DC5V;Detection voltage: less than or equal to DC5V;Capacity measurement range: 0~99999mAh;Battery internal resistance measurement: support;Measurement error is about 10%;Display real-time voltage/power/current: support;Discharge load: 10W.
ApplicationsThe 18650 battery capacity tester is specially used to check the capacity, internal resistance, voltage, current, power and other information of the 18650 battery.The integration of charge and discharge saves the tedious operation of disassembling and assembling the battery when replacing the equipment
The 1.77 inch screen simultaneously displays information such as internal resistance, capacity, voltage, current, and battery level, providing comprehensive data for analysis

Show Price

9.5

FNIRSI

FNIRSI HRM-10 Voltage Internal Resistance Battery Tester, Milliohmmeter 100V 200Ω, Car Battery Tester, Battery Checker Tester for All Types of Batteries, AAA AA Battery, Household Battery Analyzer

Free Shipping

Main Highlights

Upgrade Tester Clamp ProbeCompatible with All Battery Types. Easily test car battery tester, household battery, AA, AAA, and more using different tools
Voltage Internal Resistance Battery TesterFNIRSI battery tester can automatically test internal resistance and voltage value at the same time. The measured value can be used to determine whether the battery quality has decreased
Milliohm MeterDesigned for professionals on the go, this lightweight, compact device delivers accurate low-resistance measurements, making it ideal for detailed battery diagnostics across various environments
Measuring RangeThe resistance measurement range is up to 200 and the voltage measurement range is up to 100 V. The device must not be used with a DC voltage higher than 100V. Do not apply AC voltage under any circumstances
TFT HD Color DisplayThe display adopts advanced color HD technology and excellent layout. Compared with traditional monochrome displays, it can present test results more clearly and vividly, greatly enhancing the user's measurement experience
Accurate MeasurementAdopts customized Kelvin four-wire connection method to avoid wire and contact resistance and improve measurement accuracy. Users can also manually adjust the voltage and resistance range
Log & Export Measurement DataIt supports historical records and export data tables of historical measurements. View 8 sets of voltage and resistance values. Easily compare measurement results

Show Price

9.2

ZORZA

ZORZA 1Pcs Type-C 18650 Battery Capacity Tester Lithium Battery Internal Resistance Tester 4-Channel Automatic Charge Discharge Module for Flat Ends 18650 Batteries

Free Shipping

Main Highlights

Our battery tester supports independent 4-channel internal resistance and capacity measurements, allowing you to accurately assess your batteries.
It features a charging function with automatic cutoff when the batteries are fully charged, ensuring their safety and longevity.The discharge function automatically stops when predetermined conditions are met, preventing over-discharging.In automatic charging mode, it supports up to 9 cycles of charging and discharging, optimizing battery performance.
The compact design of the 18650 battery holder supports flat top batteries and allows for easy measurement (compatible with batteries with discharge voltage between 2.5V and 3.5V, and charging voltage at 4.2V).Please note automatic charging and discharging function is not suitable for lithium iron phosphate batteries.
Switching between Chinese and English interface: Press and hold the "Menu/M" button while powering on. Release the button when the screen lights up. After turning on, wait for 10 seconds before disconnecting the power. When powered on again, the language switch will be completed.
This battery tester operates on a DC5V power supply and is equipped with dual Type-C ports (power cord not included, compatible with C-type phone cables). It utilizes a direct current two-wire method for internal resistance measurement and provides status indicators. It also offers high-temperature protection and active heat dissipation.

Show Price

9.0

DWEII

DWEII 8-Channel 18650 Lithium Battery Auto Charge/Discharge Tester Capacity Internal Resistance Tester 2.4-in Screen DC 5V

Free Shipping

Main Highlights

Only support charging-discharging-charging 1 cycle in automatic mode, do not support multiple cycles. support external test,can be discharged through the 2P terminal external, a single channel single time only and can only support the battery holder or external test in one, can not be used at the same time the battery holder and external battery test
Channel type: 8 independent channels, each unrelated, independent operation, without mutual influence(User manual available if do as follow: click "DWEII"(you can find "Sold by HANXI01" under Buy Now button), in the new page, click "Ask a question".)we will send you the manual asap
The 18650 battery holder is only applicable to flat-head 18650 battery test. It is not applicable to pointed-head 18650 or other specifications of battery test. Before use, adjust the spring piece and the tightness with pointed-nose pliers.
DC5V/10A power supply with sufficient power must be used for power supply; otherwise, the equipment cannot operate normally due to insufficient power supply;2.4-inch color display: Equipped with a high-definition 2.4-inch color screen, data is clearly visible and operation is intuitive and convenient.
Charging mode: program start ~ charging voltage is set to 4.2V, charging current is less than the stop current for 30 seconds, the programme ends (charging voltage is not equal to 4.2V, the battery voltage reaches the charging voltage, the programme ends) ~ charging is complete.

Show Price

8.8

X-cosrack

Universal Battery Checker Tester with Leads LCD Display, Battery Capacity Voltage Resistance Tester for AAA AA C D 9V Digital 12V 3.7V Li-ion 18650 CR123A CR2032 Button Cell Batteries More

Free Shipping

Main Highlights

HIGH COMPATIBILITY: This digital battery tester fit for all common batteries from small to large- 1.2V 1.5V NIMH Alkalilne AAAA, AAA, AA, A, C, SC, D battery 9V (6LR61/LR61) battery, 3.7V 3.2V 3.0V Li-ion LiFePO4 Lithium 10440, 16340(123A), CR2, 18650, 26650, 32650 etc, CRV3, 2CR5, 1.5V 3.0V Lithium alkaline button cell, 1.5V hearing aid batteries A13 A10, A675, A312, 3.0V various Lithium button cell (CR2032 CR2025 CR2016 CR1025 etc); 1.5V various alkaline primary button cell (AG1 AG10 AG13 AG11 etc), perfect household battery tester for all kinds of primary batteries and rechargeable batteries.
CLEAR LCD SCREEN: Easy to read the state of your battery, it will analyze whether your battery is good or not or whether they need to be charged; compact and lightweight tool, portable handheld tester.
MULTI-FUNCTIONAL TESTER: This battery checker tester can not only detect battery capacity percentage level precisely, but measure the voltage and internal resistance of household battery, equal to simple multimeter. Capacity percentage indicates battery power is high or low, and resistance reflects whether battery quality is good or not, smaller resistance, better battery.
EASY TO USE: Just switch corresponding voltage and use leads to test, no need to insert battery into slot; the digital tester will quickly show the status of your batteries health, helps to avoid battery damage from overcharging. POWERED by 2 NON-RECHARGEABLE AAA ALKALINE BATTERIES.
TIPS: What you get is a universal battery checker tester (2 AAA batteries not included). If you have any questions, don't hesitate to contact us.

Show Price

8.6

ZORZA

ZORZA 1Pcs Dual-Channel 18650 Battery Internal Resistance Tester Accurate Battery Capacity Tester Master Your Battery Health & Capacity with Auto Charge-Discharge & Type-C Power Module DC5V

Free Shipping

Main Highlights

Unleash the full potential of your 18650 lithium batteries with our state-of-the-art 18650 Battery Internal Resistance Tester. Precision-engineered for accuracy and reliability, this multifunctional device is your go-to solution for comprehensive battery health assessment, including capacity testing. Powered by DC5V via a Type-C interface, it's designed for the discerning electronic enthusiast, battery maintenance professionals, and engineers alike
Innovatively utilizing a direct current 2-wire method, our Battery Health Tester delivers high precision in full-charge condition measurements, making it ideal for comparative analysis among batteries of the same batch. Catering to a wide range of applications, from home use to workshops, it's the perfect tool for ensuring your batteries' performance and longevity
Our battery capacity tester is versatile and user-friendly, supporting a broad spectrum of battery voltages from the cessation of discharge voltages between 2.5V to 3.5V. With discharge currents up to approximately 1A, it is suitable for almost all batteries meeting the voltage range of 2.8V to 4.2V, providing a thorough and reliable battery management system
Designed with convenience in mind, our TypeC Battery Testing Module offers 11 adjustable discharge stop voltages from 2.5V up to 3.5V. Together with a specialized battery charging chip, it ensures optimal charging performance up to approximately 1A, automatically stopping once the charging current dips below 0.1A at a full charge voltage of 4.2V
Ensure the peak performance and health of your batteries with our robust 18650 Lithium Battery 2-Channel Capacity Automatic Charging and Discharging Module. It's not just a tool but a comprehensive solution tailored for enthusiasts who demand precision, reliability, and versatility in their battery maintenance and testing tasks

Show Price

8.3

ACEIRMC

Type-C 18650 Lithium Battery Capacity Tester 8 Channel MAh MWh Digital Battery Power Detector Module Internal Resistance Tester Support Automatic Charge Discharge

Free Shipping

Main Highlights

18650 battery holder using compact battery holder, suitable for flat battery measurement.Voltage and current curve display, real-time voltage and current, DC two-wire method to measure internal resistance, only for the same batch sorting analogy
8 independent channels, each unrelated, independent operation, without mutual influence.support 8 channels to set up synchronisation, also can set up each channel parameter individually
Type-C 18650 Lithium Battery Capacity Tester 8 Channel Module Working voltage: DC5V 10A (standard bare metal, without power supply), overpressure must burn machine.Power supply reverse protection,prohibit reverse power supply
Only support charging-discharging-charging 1 cycle in automatic mode, do not support multiple cycles. support external test,can be discharged through the 2P terminal external, a single channel single time only and can only support the battery holder or external test in one, can not be used at the same time the battery holder and external battery test
The blue segment at the upper end is the external discharge terminal, and the lower end has the working indicator of the corresponding channel.U-shaped groove at the back is combined with PCB board, and the fan actively dissipates heat to form a heat dissipation channel

Show Price

8.1

AITIAO

AITIAO 1Pcs Type-C 18650 Battery Capacity Tester Lithium Battery Internal Resistance Digital Display Detector 1-Channel Automatic Charge Discharge Module for Flat Ends 18650 Batteries

Free Shipping

Main Highlights

Supply Voltage: DC5-12V lithium battery (not include)Measurement Accuracy: 1mAHStandby Current: 5mADischarge Current: About 500mALoad Power: 10W 8
LCD Display: The 1.77in screen displays internal resistance, capacity, voltage, current, power and other information at the same time.
This battery capacity tester is mainly used for test the capacity of 18650 battery.
This battery tester operates on a DC 5V power supply and is equipped with dual Type-C ports (power cord not included, compatible with C-type cables). It utilizes a direct current two-wire method for internal resistance measurement and provides status indicators. It also offers high-temperature protection and active heat dissipation.
Stop discharge voltage: 2.5V, 2.6V, 2.7V, 2.8V, 2.9V, 3.0V, 3.1V, 3.2V, 3.3V, 3.4V, 3.5V, a total of 11 adjustable gear.

Show Price

8.1

KOOBOOK

KOOBOOK 1Pcs Type-C 18650 Lithium Battery Capacity Tester 8 Channel MAh MWh Digital Battery Power Detector Module Internal Resistance Tester Support Automatic Charge Discharge

Free Shipping

Main Highlights

18650 battery holder using compact battery holder, suitable for flat battery measurement.Voltage and current curve display, real-time voltage and current, DC two-wire method to measure internal resistance, only for the same batch sorting analogy
8 independent channels, each unrelated, independent operation, without mutual influence.support 8 channels to set up synchronisation, also can set up each channel parameter individually
The blue segment at the upper end is the external discharge terminal, and the lower end has the working indicator of the corresponding channel.U-shaped groove at the back is combined with PCB board, and the fan actively dissipates heat to form a heat dissipation channel
Only support charging-discharging-charging 1 cycle in automatic mode, do not support multiple cycles. support external test,can be discharged through the 2P terminal external, a single channel single time only and can only support the battery holder or external test in one, can not be used at the same time the battery holder and external battery test
Working voltage: DC5V 10A (standard bare metal, without power supply), overpressure must burn machine.Power supply reverse protection,prohibit reverse power supply

Show Price

Our Best Overall Choice

Best Choice

9.7

FNIRSI

FNIRSI HRM-10 Voltage Internal Resistance Battery Tester，Battery Voltage Meter for Types of Batteries, Car Battery Tester, AAA AA Battery, 100V 200Ω, Digital Battery Analyzer for Household Automotive

Free Shipping

Editor's bottom line:

“This is the best one we tested. In terms of quality, brand and price, we couldn't ask for more.”

Main Highlights

Voltage Internal Resistance Battery TesterFNIRSI battery tester can automatically test internal resistance and voltage value at the same time. The measured value can be used to determine whether the battery quality has decreased
TFT HD Color DisplayThe display adopts advanced color HD technology and excellent layout. Compared with traditional monochrome displays, it can present test results more clearly and vividly, greatly enhancing the user's measurement experience
Accurate MeasurementAdopts customized Kelvin four-wire connection method to avoid wire and contact resistance and improve measurement accuracy. Users can also manually adjust the voltage and resistance range
Wide Application RangeSuitable for all kinds of batteries. Car battery tester, household battery. It supports historical records and export data tables of historical measurements. View 8 sets of voltage and resistance values to batch select batteries
LED Display Handheld MeterThe resistance measurement range is up to 200 and the voltage measurement range is up to 100 V. The device must not be used with a DC voltage higher than 100V. Do not apply AC voltage under any circumstances

Show Price

Deals are Live

Special Amazon deal ends in: