leagend Takes Winter Starting to the Next Level with JS300 PRO and JS300 PRO-D on Kickstarter

Designed for temp from −40°C to 80°C, leagend JS300 PRO and PRO-D combine battery-free starting assistance and smart battery monitoring for everyday drivers.

DETROIT, MI, UNITED STATES, October 12, 2026 /EINPresswire.com/ -- As winter approaches and cold weather puts additional demands on vehicle starting batteries, leagend is introducing a different way for drivers to prepare for unexpected starting problems. Now live on Kickstarter, the leagend JS300 PRO and JS300 PRO-D combine battery-free SuperCap technology, intelligent battery monitoring, and permanently installed starting assistance in a system designed for everyday driving and challenging weather conditions.
Unlike conventional portable jump starters that rely on built-in rechargeable batteries and need to be charged, stored, and retrieved when required, the JS300 series is designed to remain installed in the vehicle and connected to its starting battery. This integrated approach aims to make starting assistance more convenient while giving drivers ongoing insight into their vehicle's battery condition.

Designed for Winter and Beyond
Cold weather can make starting more demanding for vehicle batteries, particularly when a battery is aging or already in a weakened condition. For drivers facing frosty mornings, winter commutes, or journeys through regions with severe temperature changes, preparation can make a meaningful difference.
Both JS300 PRO and JS300 PRO-D are engineered to operate across a temperature range of −40°C to 80°C, making them suitable for a wide range of demanding environmental conditions. Their battery-free SuperCap technology stores energy in supercapacitors rather than relying on a built-in rechargeable chemical battery, offering an alternative to the conventional portable jump-starter design.
Permanently installed in the vehicle, the system is designed to be available when starting assistance is needed, without requiring drivers to remember to bring a separate jump starter or keep its internal battery charged. Actual starting performance will depend on vehicle configuration, battery condition, installation, and operating conditions.

More Than Emergency Starting: Smarter Battery Awareness
For everyday drivers, avoiding unexpected starting trouble is about more than having a jump starter available. Understanding the condition of the vehicle's battery can also help drivers make better-informed maintenance decisions.
The JS300 series connects starting assistance with intelligent monitoring through a smart app. Drivers can access key information such as battery state of charge (SoC), state of health (SoH), cold cranking amps (CCA), voltage, temperature, and starting performance data.
This visibility can help drivers recognize changes in battery condition and consider maintenance before a potential issue disrupts their plans. The system is also designed to help reduce strain on the vehicle's original starting battery during engine cranking, potentially supporting longer battery service life. Results will vary depending on battery health, vehicle design, driving habits, climate, and other factors.
Both models also feature Self-Learning Mode, designed to adapt to vehicle starting behavior, and Drive Mode, which manages the system's interaction with the vehicle's electrical system during operation. Together, these functions aim to make starting assistance more integrated with everyday vehicle use.

JS300 PRO vs. JS300 PRO-D: Two Ways to Stay Informed
While both models share the same core approach to battery-free SuperCap starting assistance and intelligent app monitoring, they offer different ways for drivers to access system information.

leagend JS300 PRO is designed for drivers who prefer a streamlined, app-centered experience. It provides access to key battery and starting-system information through a connected smart app, helping users monitor their vehicle without adding another onboard display.
leagend JS300 PRO-D adds a solar-assisted onboard display, giving drivers another way to view important vehicle battery and SuperCap system information directly in the vehicle. Alongside app connectivity, the display provides a more immediate, in-vehicle viewing option for drivers who prefer to see key information without relying solely on their phone.

The choice is straightforward: JS300 PRO offers app-based monitoring, while JS300 PRO-D combines app connectivity with an additional onboard display. Both are built around the same goal of making starting assistance more convenient and battery information more accessible.
Built for Everyday Drivers, Not Just Emergencies

From early-morning commutes and school runs to weekend road trips and winter travel, drivers depend on their vehicles to start when needed. A portable jump starter can be useful, but its convenience depends on whether it is charged, accessible, and ready to use.
The permanently installed JS300 series offers another approach: starting assistance integrated into the vehicle, with intelligent monitoring available as part of the ownership experience. Rather than focusing only on what happens after a starting problem occurs, leagend aims to help drivers stay more aware of battery condition and better prepared for changing driving conditions.

The products are intended for drivers seeking a more integrated alternative to traditional portable jump starters, as well as automotive technology enthusiasts interested in battery-free SuperCap technology and smarter vehicle systems.

Now Live on Kickstarter
The leagend JS300 PRO and JS300 PRO-D Kickstarter campaign runs from October 9 to November 22, 2026. Potential backers can explore the two models, compare their features, and review the available campaign rewards.
For drivers preparing for winter, the JS300 series offers an opportunity to explore a different concept in vehicle starting—one that brings SuperCap technology, intelligent monitoring, and permanently installed starting assistance together in a single system.
Cleck to discover the project and explore backing options here: leagend JS300 PRO: One System. Two Ways to Start.


About leagend
With more than 20 years of experience in automotive electronics, leagend, a top manufacturer of automotive battery solutions, develops products including battery testers, battery monitors, battery chargers, OBD II diagnostic tools, thermal imagers, and battery-free SuperCap jump starters. Through continued product development and engineering, leagend aims to deliver practical automotive solutions for drivers and partners in global markets.
Business Inquiries: marketing@leagend.com

Arthur Kingsly
Shenzhen leagend Optoelectronics Co., Ltd.
+ +86 755-8282 1859
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