Best 21700 Battery Charger-Introduction, Charging Hours and Usage

21700 batteries are lithium-ion rechargeable batteries that are used in some portable electronic devices and vaping accessories. The batteries generally have a higher capacity and power output than the 18650 batteries. Many people see these batteries as an upgrade of the 18650 Lithium-ion batteries thanks to their high capacity and power rating. To get the best out of these batteries, you need to charge them using the right charger.

There are several factors that you have to look at while choosing the right battery charger for your 21700 batteries Some of these include the following;

• Charging speeds: Some chargers have variable charging current that normally ranges between 0.5A to 2A. So, one chooses the current based on the battery they are charging and how fast they want it to charge. The more the charging current, the faster the battery will charge. But before you lower or increase the charging speed of the battery, you must consider the maximum continuous discharge current of the battery to know whether it can handle a specific amount of current without heating up.

• Safety of the charger: Some chargers are designed to stop charging the 21700 cells as soon as the cells reach full charge capacity. These are the chargers I would recommend especially if you don't intend to monitor the batteries while they are being charged. Such chargers also have a display that shows the percentage of the battery, voltage, charging current, etc.
  

• The number of battery slots: Different chargers have a different number of battery slots which determines the number of batteries you charge at a time. The more the number of slots, the more the batteries that can be charged at a time. So, if you intend to charge a good number of batteries concurrently, make sure you get a battery charger that has as many battery slots as possible. Most of them come with at least 2 or 4 slots.
  

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What is the best 21700 battery charger?

The best 21700 battery charger is one that charges the 21700 batteries in the safest possible way but also within a short time interval. Most of the recommended battery chargers are those that have an adjustable charging current which gives you room to adjust how much current you want the battery to draw from the charger. Below are some of the battery chargers I would recommend for charging 21700 batteries

1.MiBOXER Smart Universal battery charger

This is a universal battery charger that can be used to charge a wide range of battery types including 21700 batteries. It has 4 battery slots, so one can charge up to 4 batteries at a time. It is a smart battery charger so it has the capacity of detecting a damaged battery. If the battery is faulty, it will display an error and also stop charging that battery immediately. The maximum charging current for this charger is 1.5A. You can get yourself this charger for as low as $29 on Amazon

2.XTAR X4 2A Fast AC power battery Charger

This is a fast battery charger that can charge 21700 batteries of 2500mah capacity within 1.5 hours. It is also a universal battery charger that charges a wide range of batteries including 21700 batteries. This battery charger also has a USB type C output that can be used to charge smartphones. It also has a display that is meant to show the charging percentages and other charging information. The charger also has 4 charging slots with two of them have 2A charging current. This battery charger is available on Amazon at $32

3.MiBOXER 8-Bay Smart universal battery Charge

This is also a universal battery charger that can be used to charge 21700 batteries. It has 8 battery slots which make it suitable for people that would want to charge a large number of batteries at a go. The maximum charging current for each slot is 1.5A. It also has a smart system that can detect a faulty battery and then stop charging it immediately. When a faulty battery is detected, an error message will be shown on its display. You can get yourself this battery charger from Amazon at only $42.

How long does a 21700 battery take to charge?

The time a 21700 rechargeable battery takes to charge depends on how fast the charger being used is and the capacity of the battery. 21700 batteries typically have capacities ranging between 3000mAh to 5000mAh. For instance, you can charger a 3000mAh battery using a 2A charger within 1.5 to 2 hours. If you use a charger with 1A, the charge time will go up to 3 or 4 hours.

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Using lower Amps chargers reduces the chances of causing damage while the battery is being charged. Batteries also last longer when they are charged with a slightly lower current. So, if you're not in a rush to fill up the battery, you should use a 1A charger to juice up your batteries. This will increase the charge cycles of your battery which will save you money in the long run.

How do you use 21700 battery chargers properly?

The way you use your charger affects the safety of the charging process and also the durability of the battery. Before deciding on the charger to use, you must know the maximum continuous discharge current of the batteries you intend to charge. This will help you get a charger with the right current to charge the batteries without causing any damages.

Most of the battery chargers have several charging slots that vary in charging currents. You need to place the battery in the right charging slot so that it gets the right amount of current. You also need to avoid leaving the batteries on charge for long hours. Most of the chargers have a display that is mainly meant to show you the charging details of the battery. It is a good habit to always remove the batteries from the charger when they are fully charged.