The IMREN 21700 3750mAh 40A Rechargeable Lithium Battery is a high-performance energy solution designed to power high-drain devices with efficiency, reliability, and safety. With a substantial 3750mAh capacity, this battery ensures extended runtime, making it an ideal choice for applications that demand consistent power output. Whether used in vaping devices, high-performance flashlights, power tools, or other electronics requiring sustained high current, the IMREN 21700 is engineered to deliver seamless operation while maintaining stability and longevity.

Designed with a 40A continuous discharge current, this battery is tailored for high-drain applications where a steady and powerful energy supply is essential. Unlike standard lithium-ion batteries that struggle to sustain heavy loads, the IMREN 21700 ensures smooth and uninterrupted power delivery throughout its cycle. With a nominal voltage of 3.7V and a maximum charge voltage of 4.2V, it provides a balanced and steady energy output, ensuring that devices operate at optimal performance levels without power fluctuations. The advanced lithium-ion chemistry used in this battery enhances both its efficiency and safety, minimizing risks associated with overheating, overcharging, and short circuits.

Safety remains a top priority in the design of the IMREN 21700 3750mAh 40A battery, with high-quality materials and an advanced internal structure that prevents overcharging, over-discharging, and excessive current draw. This level of protection makes it a reliable choice for users who require high-performance and secure battery solutions. Rigorous quality control and testing ensure that each unit meets the highest safety standards, providing peace of mind for professionals and everyday users alike.

The flat-top design of this battery enhances its compatibility with a wide range of devices, making it a versatile power solution. Measuring 21mm in diameter and 70mm in height, it conforms to the standard 21700 battery size, ensuring a seamless fit in various electronics. This adaptability allows it to be used in high-powered flashlights, electronic toys, medical devices, and other battery-operated tools requiring a stable power source.

One of the standout features of the IMREN 21700 3750mAh battery is its rapid charging capability. Utilizing the CCCV (constant current, constant voltage) charging method, it achieves a full charge within 2 to 3 hours, ensuring minimal downtime between uses. With a charge current of 1.50A and a cut-off at 150mA, it is optimized for safe and efficient recharging, preventing overcharging while extending the overall lifespan of the battery. The battery maintains a low internal impedance of 13-16mΩ, which contributes to energy efficiency and reduced heat generation, making it ideal for extended use.

Durability is another key factor that sets this battery apart. The IMREN 21700 3750mAh 40A is designed to withstand extreme conditions, operating efficiently in charging temperatures between 0°C and 45°C and discharging temperatures from -20°C to 60°C. This resilience ensures that the battery performs reliably in harsh environments, whether indoors or outdoors. For storage, it is recommended to keep the battery at temperatures between -20°C and 45°C with a humidity level of ≤75% RH to maintain its longevity and performance over time.

Weighing approximately 55 grams, the IMREN 21700 battery is lightweight yet highly energy-dense, making it a powerful yet portable energy source. It comes with secure storage options, as each unit is packaged in a transparent plastic insulated case, allowing for safe transport and easy organization. This protective case ensures that the battery remains in optimal condition, whether stored for long periods or used as a backup power source for emergencies.

With its high-discharge capability, stable energy output, and enhanced safety features, the IMREN 21700 3750mAh 40A Rechargeable Lithium Battery is the perfect choice for users seeking a reliable, long-lasting, and high-performance power solution. Whether used for demanding professional applications or everyday electronics, this battery ensures consistent energy delivery, extended runtime, and outstanding efficiency. As a rechargeable lithium-ion cell, it also promotes sustainability by reducing the reliance on disposable batteries, offering a cost-effective and eco-friendly alternative that benefits both users and the environment.

SPECIFICATION

SHIPPING
The final shipping cost and estimated delivery timeframe will be available to you during checkout. Currently, we offer 3 International shipping methods which are steady and easy to track. Priority worldwide shipping, Premium ( Partial countries) and a faster Express shipping. The estimated times stated below are not guaranteed. An international package could experience delays like postal strikes or severe weather or Cov-19 situation. All shipping ways, PO Box address is not acceptable.

For some flashlights, there's a pure battery inside（phone charging）,If We can not ship your packages via USPS or DHL,we'll ship your package in another way.

Note:
When you place an order for just the batteries, for easy shipping, faster and safe delivery, the batteries are placed in the flashlights.

If you don’t receive your order within the estimated time frame provided below and suspect that it might be lost in transit, please contact Flashlightgo Support ( support@flashlightgo.com ) and we can look into the order with the courier. Lost-in-transit requests must be submitted to Flashlightgo Support within 3 months of the date of shipping or before the courier archives the tracking information.

Option 1.
Express by DHL/UPS/Fedex/Aramax/SF etc ( there may be tax need to pay in this way),
The estimated time of delivery is usually 3-7 work days depending on the country. Includes detailed tracking and confirmation of delivery.

Option 2.
Premium ( 6-10days, All tax and Duty Paid),
All tax and duty are prepaid to carrier by Flashlightgo before shipping, so you dont need to pay any tax or duty when you get it.

Option 3.
Priority shipping(1-2 Weeks, average 10 days)
If we marked it is with all tax and duty paid, all tax and duty are prepaid to carrier by Flashlightgo before shipping, so you dont need to pay any tax or duty when you get it.

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To ensure that you get the desirable product, we allow a seven-day product return period. Any product return application outside this period will not be entertained.
All returned product must be unused and the original package should be kept.

Return：
We do not offer return for personal products like socks and hats or food, magazine and fragile or dangerous products The original receipt must be available for application of return.

Discount products：
No product return for discount products

Gifts products：
If the item is marked as a gift when purchased and shipped directly to you, it cannot be exchanged , refunded or warranty.

Exchange：
We only replace items if they are defective or damaged.
Exchange service are offered only to wrong deliveries or product damage not caused by client. If needed, please email to info@flashlightgo.com.

Warranty
How long is the warranty period?
Flashlightgo warrants to the original purchaser that the Product(s) shall be free of any defect in material or workmanship for a period of one year for labor and one year for parts from the date of the original order except the items listed below:
Chargers,Batteries and Other Accessories: 3 months warranty

Should the Product(s) supplied by Flashlightgo prove defective because of improper workmanship or material as reasonably determined by us, Flashlightgo agrees, at its option, to either repair or replace the Product free of charge, excluding any shipping or handling charges.

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