18650 lithium batteries are mostly used in notebook computer batteries due to their large capacity per unit density. In addition, because 18650 has very good stability at work, they are widely used in major electronic fields: commonly used in high-end strong light Flashlights, portable power supplies, wireless data transmitters, electric thermal clothing, shoes, portable instruments and meters, portable lighting equipment, portable printers, industrial instruments, medical instruments, etc.

So how to choose a high-quality 18650 lithium-ion battery? Choose the most suitable 18650 lithium battery according to our electrical equipment, such as the appropriate brand, voltage, capacity, continuous discharge rate, battery life, etc. The most important thing is to choose a battery with high safety. Below we will introduce them in detail:

1. Brand

As for brands, the most reliable ones are Sanyo, Samsung, SONY, LG and other internationally renowned brands. Sanyo and LG focus on routines, and their applications are mainly bright flashlights, power banks, and laptop batteries. SONY professional, the main power and high current. Taking VTC4 as an example, the discharge current can reach 30A, and it can easily handle electronic cigarettes, toys, etc.

2. Nominal capacity

The nominal capacity of the 18650 battery is related to the battery life. The unit is “mAh”. The higher the capacity, the stronger the battery life. For example, a 2800mAh battery can be continuously discharged for 2 hours at a current of 1.4A.

3. Continuous discharge current (CDR)

Continuous discharge capacity is expressed by C number, continuous discharge current = continuous discharge capacity C number × capacity. For example, the capacity of a 18650 battery is 2800mAh and the continuous discharge capacity is 0.5C, then the continuous discharge current = 1.4A. If the discharge exceeds 1.4A for a long time, the battery life will be seriously affected, and there may be dangers of overheating, even burning, explosion, etc. .

5. Internal resistance

The internal resistance is the resistance of the battery itself. The smaller the internal resistance, the lower the consumption and the stronger the discharge capacity. The parameter of internal resistance is usually written on the battery introduction page. You should also pay attention to it when purchasing. Try not to use it. Buy more than 100mΩ or more cells. If you use multiple 18650s in series, you must buy batteries of the same brand and type, otherwise batteries with large internal resistance and low capacity will become a short board.

6. Temperature

Temperature is a major factor affecting the life of 18650 lithium battery. The higher the temperature, the faster the battery will age, and the higher the temperature, the greater the damage to the battery.

7, pointed and flat

The 18650 lithium battery also has a flat head and a pointed head. The positive electrode on the left side has a protruding point, and the positive electrode on the right has no protrusions. It is a flat head. In general, I recommend buying pointed batteries to ensure compatibility with more devices and uses. Usually, the positive and negative poles of the flashlight are designed with springs, which can be retracted and can be used whether it is a pointed or flat battery. But if you want to use a flat head battery in series, the positive pole of the flat head cannot touch the negative pole of the other battery.

8. With and without protective plate

The pointed 18650 has a protective plate, and the flat 18650 does not have a protective plate. The 18650 lithium battery with a protective plate is a few mm higher than the 18650 lithium battery without a protective plate, and the price is slightly more expensive, but it is safer and more versatile. The 18650 lithium battery with a protective plate can prevent the battery from being over-discharged. Lithium batteries are hot, and even dangerous to burn and explode.

Among all 18,650 lithium-ion batteries, LiSOCl2 has the highest energy density and can last up to 15 to 20 years. This type of battery is particularly suitable for devices with small and relatively short supply currents. The ambient resistance of the battery is also good due to its long battery life and low self-discharge rate.

When used for long periods of time, lithium polymer batteries can experience catastrophic failure. These fires can result from thermal runaway, an exothermic reaction within the cell, which results in overheating and boiling of the pyrophoric liquid electrolyte. This process can cause the casing of the battery to explode, as it has in many cases in consumer electronic devices. But luckily, there are many safety features built into these batteries to help prevent this from happening.

One of the biggest dangers of lithium polymer batteries is the risk of fire. While lithium is not considered flammable, the anode material is, typically, graphite. However, the flammability of the battery’s electrolyte is comparable to that of gasoline. The solution for this potential hazard would be a non-flammable electrolyte, which would greatly reduce the risk of fire. Still, a large amount of heat is still required for a battery to catch fire.

While a lithium polymer battery can explode, it is unlikely that the ensuing fires will kill anyone. The main dangers of these batteries are the potential for short circuits, high temperatures, and improper storage. As a result, batteries must be tested regularly to ensure that they will not overheat and cause an accident. While some lithium polymer batteries can explode due to overcharging, most won’t.

While lithium polymer batteries may not explode, a common cause for them to fail is overcharging. This occurs when a high voltage is applied across the cells of the battery. For normal lithium polymer batteries, the charging voltage should be 4.2V or higher. Any higher will trigger a chemical reaction that will produce gas and heat. If the cell walls become swollen, the battery will eventually burst and cause an explosion.

In the past, some lithium polymer batteries were known to explode at high temperatures. Fortunately, they never exploded in any way. The battery’s packaging was not the only cause of the explosions, which were caused by faulty cells. The outer packaging of a lithium polymer battery can be deformed and shattered, but a full-charged battery can still experience a dangerous explosion.

Another cause of battery explosions in lithium polymer batteries is the improper handling of the batteries. It is important to follow proper procedures to avoid this problem. For example, if you’re storing the batteries in an area with hot weather, be sure to store them in an area where temperatures will be low enough for the batteries to last for an extended period of time. This prevents accidents in your home, and is crucial for ensuring the safety of your family and your home.

1. Charge retention capability.
The charge retention capability is usually referred to as self-discharge, which usually refers to the retention capability of the battery stored in the corresponding environmental conditions in the open circuit state. Self-discharge is mainly determined by various factors such as lithium battery materials, manufacturing processes, and storage conditions. Generally, the higher the temperature, the greater the self-discharge rate. The corresponding degree of self-discharge of the rechargeable battery is a normal phenomenon
2. Internal resistance.
The internal resistance of a battery usually refers to the resistance to current flowing through the interior of the battery. The internal resistance of the rechargeable battery is very small, and it is necessary to use a special instrument to accurately measure the more accurate conclusion. Under normal circumstances, the internal resistance of the battery is the internal resistance in the charging state, even if the internal resistance of the battery is fully charged (corresponding to the internal resistance in the discharging state, which refers to the internal resistance after the battery is fully discharged. Generally speaking, the internal resistance in the discharging state The resistance is larger than the internal resistance in the charging state, and at the same time, it is not stable). The greater the internal resistance of the battery, the more energy the battery itself consumes, and the lower the battery’s use efficiency.
4. Capacity.
Refers to the total power that the battery can release under the corresponding discharge conditions.
5. Safety performance.
It is impossible to accept batteries with poor safety and reliability performance indicators. The most influential among them are explosions and leaks. The occurrence of explosion and liquid leakage is mainly related to the internal pressure, structure and process design of the battery, as well as incorrect operation.

In today’s China, there are thousands of international famous brands of electric vehicles on the market at this stage, and the two factions of electric vehicles with lead-acid batteries and lithium batteries have their own characteristics and advantages. Although electric vehicles are rapidly transforming For so many years, many people have been confused about the choice of batteries for a long time, and they do not know what the difference between the two is. Well, today we will talk about the difference between lead-acid batteries for electric vehicles and lithium batteries for electric vehicles.

The difference between lead-acid and lithium battery electric vehicles.

1. The appearance design of lithium battery is better than that of lead-acid battery.

Lithium batteries need to be much smaller in size and quality than lead-acid batteries. In most cases, the total weight of lead-acid batteries is 16-30 kg, and the size is relatively large; while the total weight of lithium batteries is 3 in most cases. -3.0KG, the body is relatively small, so it is light for riding and convenient for shipping. In most cases, lithium battery electric vehicles are light and beautiful, easy to move, and many lithium battery electric vehicles can also be folded.

1. Durability and battery life:

The service life of lead-acid batteries is usually 2 years, while lithium batteries are more durable, with a lifespan of 4-5 years; and lead-acid batteries are usually fully charged and discharged within 300 cycles, while lithium batteries are fully charged and discharged. more than five hundred times.

2. Volume quality and ease of operation.

Compared with the lightweight body of only 2.5/3 kilograms of lithium batteries, lead-acid batteries of the same capacity usually weigh about 16/30 kilograms; not only the battery quality is relatively large, but also the volume; The disassembly design makes it more convenient and quick to carry.

3. Market price and cost performance.

At this stage, the mainstream lead-acid batteries on the market are about 450 yuan, while the price of lithium batteries is more expensive at 1,000 yuan; the prices of the two types of batteries are different, and the corresponding electric vehicle prices are also relatively different. At the same time, the warranty period of lithium battery is 1 year longer than that of lead acid, and the warranty period is 2 years.

4. Cruising range and battery capacity.

The same is a 48V battery. Under the condition of full power, the cruising range of lead-acid/lithium battery electric vehicles is almost the same. In fact, the key lies in factors such as speed and motor size. Naturally, lead-acid batteries will slightly exceed lithium batteries in terms of battery capacity.

In general, lead-acid batteries are the most numerous. The price of lead-acid batteries is the lowest and most common. China is the largest producer and exporter of lead-acid batteries in the world. It contains relatively few polluting components and has good recyclability. The disadvantage is that the specific volume is small. In other words, under the same capacity, the battery weight and volume are large. At this stage, most of the lead-acid batteries are transformed from floating charge batteries. Float rechargeable batteries reject fast charging and high-current discharge. Although professional and technical personnel have spent a lot of effort and made fruitful improvements, they can be put into practical use, but their lifespan is still very unsatisfactory. Which one is better depends on your own cost budget and needs. However, considering that after the announcement of the new national standard national policy, electric vehicles must be changed to the registered side before they can ride on the road normally, so it is best to choose an electric vehicle that meets the standard.

To recharge the 26650 LiFePO4 battery, you need to first understand how the battery works. Normally, this type of battery takes three to six hours to fully charge. There are different types of batteries, and different charging times. Some products do not have a built-in charger. Other brands sell the batteries separately. To determine which type of battery you should use, check the manufacturer’s manual.

Some of the most common types of 26650 batteries are INR and IMR. Choosing the right one depends on the battery type and application. IMR and INR batteries are better suited for motorcycles than unprotected ones. Nonetheless, protected 26650 batteries are more expensive and have smaller capacity than unprotected versions. It is best to check the instructions and follow them carefully.

To ensure proper battery performance, purchase batteries that have the same chemistry. You should avoid using older batteries that may not be compatible with current standards. Some of the latest models have protection features that prevent overcharging. Then, make sure you get a properly sized charger. This will protect your battery and prevent the battery from overheating. Also, the battery should fit into the compartment.

The 26650 battery can be used for motorcycles, and it has a long shelf life. The 26650 can deliver up to 20 Amps continuously and 40 Amps for a short period of time. However, you should avoid disassembling or incorrectly disposing of it. You should also make sure you do not expose the battery to extreme temperatures. If not, it can overheat and catch fire. Intelligent chargers are safe for the 26650 lithium ion battery packs. You can also find them online at affordable prices.

When charging the 26650 LiFePO4 battery, it is important to be careful when using the charger. It is possible to use the same charger for other batteries, but if the charger does not have the appropriate adapter, the battery may not work properly. The batteries should be charged with a USB port. This way, you can use the battery on the go without having to worry about damaging the batteries.

If you want to use the battery as a flashlight, you can use a charger that supports both types. It is important to use a suitable charger when using a 26650. The power of a lithium cell is determined by the current it can handle. If the voltage is higher, the longer the battery will last. In the case of an 18650, you will need to buy a new adapter for a new battery.

The 26650 LiFePO4 battery is a size C lithium battery that can be recharged. These batteries can be recharged by an intelligent battery charger. This charger uses a micro-USB port to identify the battery. It can be used in the same way as the standard 26650 battery. If you don’t have a dedicated charger, you can buy one that supports both of these types.

High-drain 26650 batteries have the ability to deliver up to 40 Amps continuously and 60-70 Watts for short periods of time. Due to their low internal resistance, the voltage drop is minimal. Therefore, a high-capacity battery will deliver up to 110-140 Watts. When recharging the 26650 LiFePO4 battery, it is essential to use a smart charger that can detect the battery condition and determine whether it is in good condition.