March, 2020 - Nuranu

Lithium-ion batteries have the advantages of light weight, large capacity, and no memory effect, so they are widely used. Many digital devices use lithium-ion batteries as power sources, although their prices are relatively expensive.
Lithium-ion batteries have high energy density, their capacity is 1.5 to 2 times that of nickel-metal hydride batteries of the same weight, and they have a very low self-discharge rate. In addition, the advantages of lithium-ion batteries with almost no memory effect and no toxic substances are also important reasons for its wide application. There are also many types of lithium batteries. This article compares the two types of lithium batteries: 18650 lithium battery and 26650 lithium battery.

Both 18650 lithium batteries and 26650 lithium batteries are cylindrical lithium batteries. Combined with 18650 lithium batteries and 26650 lithium batteries, they have outstanding volume characteristics and high concentration, occupying a large market share in the sales market.

26650 lithium battery wuth the diameter of 26MM, and the length (height) is 65MM. Commonly known as lithium-ion batteries, 26650 lithium-ion batteries usually use nickel-cobalt-manganese (ternary) as the cathode material.

26650 lithium batteries are often used in large power tools, lighting devices, energy storage technology machinery and equipment, battery vehicles, ups ready-to-use switching power supplies, medical equipment and their military equipment.

What is the difference between 18650 lithium battery and 26650 lithium battery?

1. Different short-circuit capacity: 18650 lithium ion capacity is between 1200mah and 3600mah, The 22,650 lithium-ion batteries have a capacity between 3,000mah and 5,000mah.

2. Rechargeable batteries are different: 18650 lithium-ion batteries are 18mm, and 26650 lithium-ion batteries are 65mm.

3. Different reference quality: 18650 lithium ion net weight is 40g-48g, 26650 lithium ion net weight is 95-100g.

4. The capacity of the rechargeable battery is different, the capacity of 26650 is greater than 18650, and the lithium-ion ratio is the same.

5. Different application scenarios: 18650 lithium-ion batteries are used in lighting equipment rechargeable batteries, industrial production equipment lithium batteries, rechargeable battery inflatable tools, electric vehicle rechargeable
batteries, electric lithium batteries, etc.

6. The duration of the voyage is different: currently 2200, 2600, 3100mah for 18650. 400, 4200, 4500mah for 26650, so the duration is longer.

Under normal circumstances, 3.7v lithium batteries need a “protection plate” for overcharge and overdischarge. If the battery does not have a protection plate, only a charging voltage of about 4.2v is used. Therefore, the ideal full charging voltage of lithium batteries is 4.2v, and the voltage exceeds 4.2 v may damage the battery, charging in this way also needs to monitor the condition of the battery at all times. You can use 5v if there is a protective plate (4.8 to 5.2 can be used), the 5v USB of the computer or the 5v battery charger of the mobile phone can be used.

For a 3.7V battery, the charge cut-off voltage is 4.2V and the discharge cut-off voltage is 3.0V. So when the battery open circuit voltage is less than 3.6V, it should be ready to charge. It is best to use 4.2V constant voltage charging mode, you can not pay attention to the charging time. Charging with 5V is easy to overcharge and cause danger.

1. Float charge. Refers to the line charging while working. This method is usually used in backup power locations. If it is less than 12 volts, it cannot be charged, and if it is too high, it will endanger the work of the power supply circuit. Therefore, when the float is working, the voltage is 13.8 volts.

2. Cycle charging. For the battery to fully charge the recovery capacity, when fully charged, do not disconnect the battery charger for measurement, usually around 14.5 volts, and the highest does not exceed 14.9 volts. 24 hours after disconnecting the battery charger, typically around 13 volts to 13.5 volts. About 12.8 to 12.9 volts after a week. The specific voltage value of different batteries is different.