Car Battery Tester—Suitable for 6V/12V/24V, 100–2000 CCA, accurately measures internal resistance, and helps keep your car’s battery in top condition

Say Goodbye to the Embarrassment of a Dead Battery—Check Your Battery’s True Lifespan in 3 Seconds | One-Click Testing of SOH, SOC, Voltage, and Internal Resistance

Is Your Battery Still Up to the Task?
Dashcams, car refrigerators, phone chargers, interior lights… With more and more electronic devices in your car, the demands on battery capacity and quality are growing.
Have you ever encountered these situations?
Waking up in the morning to find your car won’t start
The engine idles erratically, fluctuating between high and low RPMs
The power system triggers unexplained alerts with no apparent cause

Often, the problem isn’t with the alternator or starter—it’s that the battery is “all show and no go”: the voltage appears normal, but the car stalls as soon as a load is applied. A standard multimeter can’t detect a battery’s true health status, but the BM550 can.

Key Product Features 
Why Choose the BM550?
❶ One device for all—compatible with over 95% of battery types
The BM550 can test the full range of 6V, 12V, and 24V automotive batteries, with a CCA testing range of 100–2,000 CCA and capacity support from 2Ah to 220Ah.

Supported battery types include:
Standard Lead-Acid Batteries (Normal Battery)
AGM Flat Batteries (AGM Flat Battery)
AGM Spiral Batteries (AGM Spiral Battery)
EFB (Enhanced Flooded Battery)
GEL Batteries
Suitable for: Cars, trucks, motorcycles, ATVs, SUVs, yachts, golf carts, and more.

❷ Four Core Metrics: Battery Condition at a Glance
The BM550 accurately displays four key metrics within 2–3 seconds:

Metric    Full Name    Meaning
SOH    State of Health: Percentage of remaining battery life
SOC    State of Charge: Current charge level (percent)
VOL    Voltage: Real-time voltage value
R    Resistance:    Battery internal resistance (mΩ), a key indicator for assessing the degree of aging
Results are displayed in three categories: Good, Normal, and Poor—intuitive and easy to understand, requiring no specialized knowledge.

❸ 1.8-Inch HD Screen for Clear Data Display
Equipped with a 1.8-inch HD screen, test results are displayed quickly and accurately, and remain clearly readable even in bright sunlight.

❹ Pure Copper Gold-Plated Alligator Clips: Strong Conductivity and Secure Grip
The alligator clips are made of pure copper with a gold-plated finish. They feature a wide opening range and a strong grip, ensuring more accurate measurements and more reliable contact.

❺ High-Purity Silicone Cables: Durable and Break-Resistant
Crafted from carefully selected, high-quality, eco-friendly materials, these cables feature a four-layer structure: pure copper conductors + insulation + anti-interference layer + outer silicone layer. They offer excellent flexibility, are resistant to breakage, and are built to last.

❻ Reverse Polarity Protection: Safe Even for Beginners
Built-in reverse polarity protection ensures that even if the clamps are attached incorrectly, the internal circuitry won’t be damaged, making it safe and reliable.

❼ Plug-and-play, with zero learning curve
No complicated setup required—simply clip onto the battery’s positive and negative terminals to begin testing. The battery can be tested whether it’s inside or outside the vehicle, or even when completely discharged.

Technical Specifications
Parameters: Specifications
Supported Voltage: 6V / 12V / 24V
CCA Measurement Range: 100–2000 CCA
Capacity Range    : 2Ah – 220Ah
Voltage Measurement Range: 4.9V – 32V
Test Accuracy    > 99.5%
Screen Size:    1.8-inch HD
Housing Material:    Industrial-grade ABS plastic, fingerprint-resistant and stain-resistant
Product Dimensions:    2.74 × 0.89 × 4.88 inches
Supported Battery Types: Standard / AGM (flat plate/spiral) / EFB / GEL

Applications
Everyday Car Owners: Perform regular self-checks to detect battery aging early and prevent battery failure during winter or after prolonged inactivity
Repair Technicians: Quickly diagnose battery faults and accurately determine whether replacement is necessary
Fleet Managers: Batch-test the battery status of multiple vehicles to reduce maintenance costs
Outdoor Enthusiasts: Check the battery health of RVs, ATVs, yachts, and motorcycles

Frequently Asked Questions 
Q: What types of batteries can the BM550 test?
A: It can test 6V, 12V, and 24V standard lead-acid batteries, AGM flat-plate batteries, AGM spiral batteries, EFB batteries, and GEL batteries.

Q: How long does the test take?
A: All test results are displayed within 2–3 seconds after connection.

Q: Can the BM550 test a battery that is completely dead?
A: Yes. The BM550 supports testing of deeply discharged batteries.

Q: What if I don’t understand the test data?
A: Test results are intuitively displayed in three categories: Good, Normal, and Poor. Green indicates Good, and red indicates Poor—it’s easy to understand at a glance.

Q: Will connecting the clamps in reverse damage the device?
A: No. The BM550 has built-in reverse polarity protection, so connecting the clamps in reverse will not damage the device.