leagend JS600 SuperCap Jump Starter

On-Board Version, Supercapacitor Car Battery Start Booster, 1300A Peak Current, -40°C~80℃ Start, Extend Battery Life 300%

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leagend JS600 On-Board SuperCap Jump Starter (Premium Heavy-Duty Model)– Pre-Order Now

Pre-Order Now – Expected to Ship in [Insert Date] Secure your unit today! Orders will be shipped in the order they are received. Payment will be processed immediately, and shipping will start from the expected date.
  • Instant Engine Start with SuperCap Technology : Delivers 700A to start 12V batteries instantly, perfect for mainstream sedans and SUVs below 3.0L/2.5T.
  • Smart & Safe Operation : BLE 5.3 enabled; automatically protects your car battery and electronics during every start.
  • Compact & User-Friendly : Lightweight, plug-and-play design fits neatly in your car for everyday onboard use.
  • Durable & Weatherproof : IP65 waterproof rating ensures safe operation in rain, snow, or dusty conditions.
  • Quick Charge & Low Power Standby : Recharge via car battery in 3–22 minutes or Type-C 5V/2A in 3–50 minutes; consumes only 3mA in standby.

Note: This product is available for pre-order. Shipping begins from the expected date above.

Color: Black
$419.90 USD
$419.90 USD
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What is a SuperCap Jump Starter?

leagend SuperCap Jump Starter is the Second-Generation On-Board SuperCap Jump Starter.

A SuperCap Jump Starter is an ultra-safe, maintenance-free device that keeps your car starting reliably. Unlike traditional jump starters, it uses supercapacitors instead of lithium batteries, eliminating fire or explosion risks.
Permanently installed under your hood, it activates automatically whenever your car battery is weak. Even when your battery drops as low as 5V, the SuperCap Jump Starter quickly charges itself from your car’s battery and delivers a strong burst of power in just seconds—starting your engine instantly.
Every time you start your car, it assists the battery by taking over the heavy discharge load. This ensures cleaner, stronger ignition, reduces stress on your battery, and helps extend its overall lifespan.

SuperCap vs Lithium Jump Starter

Super Capacitor Jump Starter

Super Capacitor
Physical Reaction
External Power Supply: 0-40 minutes
Car Battery: 2-10 minutes
100,000 Charge-Discharge Cycles
-40℃~80℃
★★★★★
No Risk of Bulging/Combustion/Explosion
Maintenance-free; ultra-low self-discharge
Delivers stable high current even in low temperatures
10+ years with almost zero self-discharge
Can self-charge even when the car battery is as low as 5V
Eco-friendly, no chemical pollution
Higher upfront cost, lower long-term cost

Lithium Polymer Jump Starter

Lithium Battery
Energy Storage Material
Chemical Reaction
Energy Storage Method
External Power Supply: 2-9 hours
Car Battery: 2-10 minutes
Charging Speed
500-2000
Cycle Life
-15℃~40℃
Operating Temperature
★★★☆☆
Risk of combustion/explosion at high temperatures/overdischarge prevention required
Safety
Must be recharged every few months; self-discharge occurs
Maintenance
Strongly affected by temperature, battery health, and remaining power
Instant Peak Current
Requires recharging every 3–6 months
Shelf Life / Standby
Requires sufficient internal battery charge; unreliable in cold weather
Reliability
Chemical cells require careful recycling
Environmental Safety
Lower price, but shorter lifespan
Cost

Product 8 Key Functions

Super Capacitor

1300A Peak Current
Start at 5V

Fully Automatic Ignition

Install Once
Auto Activation

It can still run even

No Charging Needed

24h

Smart App Control

Super Capacitor

-40℃ to 80℃

Super Capacitor

IP65 Waterproof

Super Capacitor

Wide Compatibility

Super Capacitor

No Battery Inside
Zero Fire Risk

Always Starts Your Car

Even in extreme cold, low voltage, or remote areas. Delivers up to 1300A peak current, ignition even at 5V.

❄Extreme Weather Ready Reliable from -40℃ to +80℃.

Protects Your Battery – Reduces strain, extends battery lifespan from 2 years → 5 years.

When starting your car, the Booster’s supercapacitors deliver the high peak current first, so your lead-acid battery doesn’t need to release large bursts of power.
-The battery only provides light support → less stress.
-Prevents deep discharge & high current damage.
-Extends battery replacement cycle, saving costs and reducing waste.
Without Booster: battery voltage drops to 8V at start → damages battery plates.
VS
With Booster: voltage stays above 11V, capacitor handles the current spike.
👉 Result: 80% less damage, battery life extended from 2 years → 5 years.

Safety First

No Battery Inside – Built with pure supercapacitors = 0 explosion / fire risk.
6 Protections Built-In – Reverse, short-circuit, overcurrent, over/under voltage, temperature.

Convenience & Smart Experience

Maintenance-Free – No charging required, always ready.
Easy Installation – Just two terminals, done once, no daily hassle.
Smart App Control (New!) – Real-time monitoring of voltage/temperature, alerts & reports, one-tap emergency start.

Durability & Sustainability

Ultra Long Lifespan – Over 500,000 starts = decades of use.
Works Automatically – Shares start-up load every time, prolongs battery health.

APP Intelligent Monitoring
Battery Health Status Alert

Key Battery Data Smart Detection

Key Battery Data
Smart Detection

Key Battery Data Smart Detection
Abnormality Alerts and Maintenance Early Warnings

Abnormality Alerts and
Maintenance Early Warnings

Abnormality Alerts and Maintenance Early Warnings
Manual Override Dual Assurance

Manual Override
Dual Assurance

Manual Override
AI Smart Learning Driving Habits

AI Smart Learning
Driving Habits

AI Smart Learning
Constantly Records

Constantly Records and
Stores Battery Health Data

Constantly Records

Minimalist Installation
in Just 4 Steps

No Harm to the Vehicle, No Wiring Modification, Even Beginners with
Zero Experience Can Install, Long-term Protection for Battery Health

1
Open the car engine compartment to locate the car battery.
Connect the wires
2
Connect the wires:
Red to the positive terminal,
Black to the negative terminal.
Secure the product with a cable tie.
3
Secure the product with a cable tie.
Secure the product with a cable tie.
4
Connect via Bluetooth and start the vehicle to test if it works.
Connect via Bluetooth and start the vehicle to test if it
Product Type
JS200

JS200
JS300

JS300
JS400

JS400
JS600

JS600
Vehicle Compatibility
Mainstream sedans/SUVs below 3.0L and 2.5T
Large-displacement sedans/SUVs below 3.5L and 3.0T
Large-displacement sedans/SUVs/performance cars below 6.0L and 6.0T
Trucks/large trucks/buses below 8.0L and 8.0T
Average power
consumption
3mA
3mA
3mA
3mA
Discharge current
700A
1000A
1300A
1300A
Charging time
3~22minutes
Type-C（5V/2A）： 3~50minutes
3~22minutes
Type-C（5V/2A）： 3~50minutes
3~10minutes
Type-C（5V/2A）： 3~40minutes
3~13minutes
Type-C（5V/2A）： 3~67minutes
number of charge
and discharge cycles
500,000 cycles of charging and discharging
100,000 cycles of charging and discharging

Patents & Certifications

SUPERCAPACITOR CONTROL CIRCUIT AND
METHOD FOR INTELLIGENTLY IDENTIFYING STARTING MODE OF VEHICLE

EU Safety Certificate
EU Safety Certificate
US Safety Certificate
US Safety Certificate

FAQ

Why can super starter extend battery life?
The starter has much lower internal resistance than the car battery. At startup, current flows through the starter, which undertakes high-current discharge. The car battery "avoids heavy work", greatly extending its life
How to operate super starter?
No operation is needed after installation; start the engine directly, and the starter works fully automatically
Is super starter suitable for cars not used for a long time? Will the starter drain the battery?
Yes, it is suitable; the average power consumption of the starter is only 3mA (much lower than the car's self-discharge, negligible), and the engine can start normally as long as the battery voltage exceeds 5V
If the car battery is dead, can the starter be installed without replacing the battery?
The starter only solves the problem of starting the engine; when the battery is dead, its power/voltage is low, and some on-board systems will detect the low voltage, prompt a fault, and may disable functions, so it is recommended to replace the battery
What if the starter fails to start the car?
1. Check whether the positive and negative connections are correct and free of looseness 2. Check the starter's power (it is recommended to be ≥80%) 3. The engine must be started within 10 seconds when using forced starting/manual discharge
How to wake up the starter when it is in hibernation?
1. After installation, it enters hibernation (indicator lights go out) after standing for 20 minutes, and can be woken up when vibration or voltage change is detected; 2. Normal engine startup can wake up the hibernating starter
How to choose the corresponding starter for 12V and 24V cars?
12V vehicles should use 12V starters (24V starters are not applicable), and 24V vehicles should use 24V starters (12V starters are not applicable); they cannot be mixed.
Will the starter self-ignite if installed on the car for a long time?
The product contains no batteries at all, so it will not self-ignite and has high safety; do not install it in the high-temperature area of the engine