EV charger – the introduction of the principle and choose

How EV charger works

The two-stage charging mode is constant voltage charging. It is to divide the charging process into two charging stages, constant current and constant voltage, and the charging current gradually decreases with the increase of battery voltage.

When a battery power rises to a certain extent, it is then converted to constant voltage charging, so that the voltage in the battery rises slowly. When battery voltage reaches the charging terminal voltage of the EV charger, it is then converted to trickle charging, that is, floating charging. This can effectively protect the battery and extend the battery life. The EV charger generally use three-stage charging.

The two-stage charging mode is constant voltage charging. It is to divide the charging process into two charging stages, constant current and constant voltage, and the charging current gradually decreases with the increase of battery voltage.

Charger charging is to pass direct current through the battery in the opposite direction to the discharge current after the battery is discharged. The process of converting electrical energy into chemical energy in the battery and storing it to restore its working capacity is called battery charging.

There are two ways to charge the battery: constant current charging and constant voltage charging. The charging voltage of the battery must be higher than the total electromotive force of the battery. The charging method is: connect the anode of battery to the anode of the power supply, and the cathode of battery is connected to the cathode of the power supply.

Classification of EV charger

The EV charger is mainly composed of plastic shell, output plug, input plug, etc. There is an indicator light on the charger, which is used as a power indicator and a charging indicator at the same time, and when using it, plug in the charging outlet plug first, and then plug in the input plug to charge.

The charging of a battery is not arbitrarily connected to the power supply can be charged, such as alternating current does not become direct current can not be charged, the size of voltage and current is not appropriate can not be charged, can not be overcharged, etc., these need to be completed by the EV charger.

The top 10 e-bike battery manufacturers have designed different features for their products. There are two structural forms of EV chargers: one is a transformer type ordinary charger, and the other is a switching power supply type charger.

Both chargers have different characteristics. At present, electric vehicles generally use switching power supply chargers, which are mainly composed of switching transformers, transistors, control integrated circuits, etc.

● Benefits of chargers with switching power supply technology

• Wide range of application: suitable for charging both lead-acid batteries and lithium batteries.
• Wide input voltage range.
• Output overvoltage protection.
• Anti-reverse connection.
• It can be short-circuited for a long time.
• Intelligent three-stage charging is adopted.
• Effectively control the output according to the size of the load, protect the load and save energy.

How to use EV charger correctly

Whether EV charger is used correctly will have a greater impact on the reliability and life of the charger, as well as battery life. Before charging the charger, plug in the charger’s DC outlet plug, and then plug in the AC 220V plug.

The general charging time is 6-8h, and it needs to be determined according to the discharge of the battery during the actual charging process. When charging an electric vehicle, the EV charger power indicator shows red, and the charging indicator light also shows red.

When the charging indicator turns green, it means that the battery is basically full. If it is not urgent, it can be floated for 1-2 hours. When stopping charging, first unplug the AC 220V plug of the EV charger, and then unplug the DC output plug of the EV charger, pay attention to the order should not be out of order.

Precautions for the use of EV charger

● Place the charger in a dry, ventilated environment.

Usually, we should pay attention to moisture-proof and moisture-proof. The charger generates a certain amount of heat when working, so it is strictly forbidden to place flammable materials, such as plastic or foam, on the bottom or around it. If you smell an odor or the charger case is too hot while charging, you must stop charging immediately.

● Prevent liquids or metal chips from entering the charger.

When using or storing the charger, don’t let water or other things enter the interior.

● Try not to carry the charger with the car.

If you need to carry it, the EV charger should be packed with shock absorbing material, placed in the toolbox on the car, and pay attention to rainproofing.

How to choose an EV charger

As the core of electric bycicles, batteries have always been one of the hot topics of concern. For EV batteries, the matching charger and correct charging operation also determine the service life of the battery. So, for EV charger, how should you choose to buy.

● Model matching

• Determine the battery voltage of the e-bike

If the charger voltage is too high, the battery will be drummed, and the charger voltage is too low, which will cause the electric vehicle to be undercharged. Therefore, when choosing a EV charger, you need to pay special attention to whether EV charger output voltage is matched. The battery voltage of common electric bicycles is 48V, 60V or 72V, and you must see bike battery voltage clearly before purchasing.

• Determine the battery capacity of the e-bike battery

Battery capacity is the last two digits of the battery model. When buying, you must see capacity of the battery, if the capacity does not match, there will be overcharge or undercharge, resulting in reduced battery life and even danger.

For example, a charger with an output current of 1.8A is used for a 48V12Ah battery, and a charger with an output current of 3.0A is selected for a 60V20Ah battery.

• Determine the appropriate charger connector shape

There are 4 kinds of common interfaces on the market: round head, three vertical plugs, one horizontal and two vertical plugs, and T-type plugs, which must match the electric bicycle interface when choosing.

● Quality assurance

• Choose a charger that meets your standards

Choose the right EV charger to effectively ensure that the battery is in a safe state when fully charged.

• Choose a branded charger

There are many brands of chargers on the market, please go to the regular brand store to buy, in terms of performance and safety will be more guaranteed.

• Choose a smart charger

Non-smart chargers, when charging, are generally charged with high current. After more than ten hours, the battery begins to heat up and may be scrapped. The smart charger can effectively ensure that the battery is in a safe state when fully charged.

Before buying an EV charger, you must understand several basic parameters, such as the voltage capacitance of the electric vehicle, so that you can buy a product that suits you. With the right EV charger, the correct charging operation and daily maintenance can not be ignored, and it is necessary to find a place that specializes in providing electric vehicle charging.

Why the charger is more likely to break

● Charger quality issues

Some users, for convenience, like to buy a low-quality or refurbished charger when replacing an EV charger, often spend a low price to buy a poor quality or refurbished charger. And this kind of charger is not visible from the appearance, and the components inside are often problematic, this charger is not only not durable, but also easy to charge the battery.

● Improper operation

Some people don’t know that electric vehicle batteries need charger matching, and often for convenience, they like to mix chargers. With long-term use, not only will the charger be damaged, but the batteries are also prone to overcharge and shorten its life.

● Charging time is too long

Many people’s electric vehicles are charged for one night or more than ten hours, which can easily lead to overcharging batteries. The charger works for a long time, resulting in large heating and damage. To protect the charger and battery and extend its life, it is best to keep the charging time within 8 hours.

● Vibration causes components to fall off

This is one of the most overlooked problems, due to the decline of electric vehicle batteries, having to carry chargers with the car. Although this is convenient for you, it often causes some problems. Because the electric vehicle will vibrate during driving, it may cause the charger components to fall off for a long time, and the charger will be damaged by virtual connections.

Conclusion

In short, if electric vehicles want to run far and use for a long time, we must not only pay attention to the maintenance of electric vehicle batteries, motors, controllers and other accessories, but also strengthen the maintenance of battery chargers, so that electric vehicles can achieve maximum utility.