What is 18650 Flat Top Rechargeable Battery?

18650 battery comes in two forms based on the shape of the positive terminal: flat-top and button-top. These refer to the shape of the battery’s positive contact surface.

Flat-Top Battery:
18650 flat-top rechargeable battery features flat positive terminal. Devices such as flashlights, remote controls, and digital cameras commonly use flat-top batteries. This flat design allows the battery to make secure contact with the device’s terminals, ensuring stable current flow and reliable device operation.

Button-Top Battery:
Button-top batteries, sometimes called “raised-head batteries,” have a protruding positive terminal. High-power devices like power tools, electric vehicles, and e-bikes often use button-top batteries. The raised terminal strengthens the connection between the battery and the device’s contacts during high-current discharges. This reduces contact resistance and prevents overheating or power loss caused by poor contact.

Device Compatibility:
One key difference between flat-top and button-top batteries is device compatibility. Some devices require a specific terminal type. When purchasing batteries, users must check the device specifications to ensure they choose the right type.

No Major Chemical Differences:
Flat-top and button-top batteries don’t differ in chemistry or capacity. Both can come in various lithium chemistries, such as lithium manganese oxide (LiMn2O4), lithium cobalt oxide (LiCoO2), or lithium nickel manganese cobalt oxide (NMC). So, when selecting a battery, users should also consider the chemistry, capacity, and other technical specifications.

Differences Between Flat-Top and Button-Top 18650 Batteries

Size and Shape:
The positive terminal of a flat-top 18650 battery is smooth and flat, while the button-top version extends about 3 millimeters higher with a visible bump. This bump helps prevent short circuits by reducing the chance of unintended contact between the battery’s positive terminal and conductive materials during installation or transport.

Battery Characteristics:
Both types of batteries offer similar capacity and performance. They share the same 18mm diameter and can often be used interchangeably based on physical size and capacity. However, most button-top 18650 batteries include a built-in protection circuit that monitors voltage and current. This circuit disconnects the battery if it detects overcharging, over-discharging, or short-circuiting, providing full protection for both the battery and device. In contrast, flat-top batteries usually lack this protection and rely on the device to provide safety features.

When selecting a battery, users should match the battery shape and features with their device’s requirements. The 18650 battery remains highly popular thanks to its excellent performance and wide range of applications. To ensure safe and efficient use, it’s essential to consider factors such as capacity, continuous discharge current, internal resistance, voltage, safety features, temperature tolerance, and cycle life. Choosing the right 18650 battery helps ensure the reliable performance and safety of your device.

Electric Bike 36V 10Ah Water Bottle Style18650 Lithium Battery Pack

September 9, 2025

High-performance 36V 10Ah water bottle lithium battery for electric bikes. Lightweight 3.5kg, fast charging in 1.5–2 hours, safe & durable with up to 500 cycles. Ideal for commuting and long rides.

18650 24V 4000mAh Rechargeable Lithium Ion Battery Pack

August 30, 2025

high-performance 18650 Battery 4000mAh, offering stable 24V power and deep cycle support. Perfect for electric scooters, power tools, and energy storage systems. Built-in safety protections ensure long-lasting, reliable performance.

ICR 18650 3.7v 2200mAh Li-ion Battery

August 18, 2025

Wholesale ICR 18650 2200mAh 3.7V lithium batteries with optional customized packs. Supports external wiring and various wire leads to meet your project-specific needs.

18650 3.7V 1500mAh Lithium-Ion Battery

August 8, 2025

18650 3.7V 1500mAh lithium-ion rechargeable batteries from China, ideal for flashlights, power banks, electric tools, and more. High capacity, long cycle life, full safety features, and customizable OEM/ODM services. Fast global shipping available.

18650 3.7V 3000mAh lithium-ion batteries

August 8, 2025

Top-quality 18650 3.7V 3000mAh lithium-ion batteries ideal for electric scooters, power tools, cameras, and more. Long cycle life, stable performance, and customizable options. Fast shipping worldwide. OEM & ODM services available.

Li ion 3.7V 2300mah 18650 Lithium Battery

August 8, 2025

High-quality 18650 3.7V 2300mAh lithium ion batteries perfect for flashlights, vape mods, electric scooters, and power banks. Long cycle life, built-in safety features, and flexible OEM/ODM customization available. Fast shipping and competitive pricing for wholesale buyers.

18650 3.7V 3300mah Lithium ion Battery Rechargeable

August 8, 2025

Buy high-quality 18650 3.7V 3300mAh rechargeable lithium-ion batteries ideal for smartphones, tablets, power banks, and electronic devices. Durable, safe, and customizable with built-in protections. OEM & ODM services available. Fast shipping for wholesale orders.

18650 2000mAh 3.7 Volt Lithium ion Battery

August 8, 2025

China-made 18650 2000mAh 3.7V lithium-ion batteries, perfect for laptops, power tools, and electric vehicles. Reliable, safe, rechargeable with customization options. Wholesale pricing and fast delivery.