When you think of the word ‘charging,' what runs through your mind? If you're like 90% of technology users, you would most likely envision your mobile phone is charged with a USB cable. But what if you’re told that there’s a lot more than that?
Who says charging has to be for portable devices alone? Who says your charger must be plugged to an electrical outlet. Who says charging can’t go both ways? There are so many questions to ask! And you can rest assured that we shall answer all your questions.
But first, we start with an in-depth explanation of charging technology for mobiles and electric vehicles, and then the concept of wireless charging, fast charging, etc. We also explore charging by contact and induction, going over circuit accuracy and voltage transformation.
When you get to the end, your knowledge of charging would’ve soared in leaps and bounds. You can thank us later.
1、Charging Technology Application
Everyday, we are charged with charging at least one of our devices. It might be your mobile phone, your personal computer, or even your cars. Yes, you can now charge your cars! This chapter will introduce you to the charging technology behind electric vehicles.
There are four different modes of charging. Let’s start by briefly going over each method.
In this mode, the vehicle is connected to the power grid via a conventional outlet, the usual one you have in your residential apartment. The installation is required to comply with safety regulations and policies. An earthing system, a circuit breaker, and other protective components guard against accidental contact.
In this case, we connect the vehicle to the main power grid using standard socket-outlets. Single-phase and three-phase systems are employed for the charging, and an earthing cable is also installed. The specific nature of the cables required make this solution more expensive than the first mode.
A special plug and socket are employed for the direct connection of the vehicle to the electrical network. Also, the control and protection function is also installed in the circuitry permanently. Load shedding is also enabled so that the normal household appliances can be used while the electric vehicle is charging.
In this mode, the car is connected to the electrical network via an external charger. The installation also comprises the control and protection functions.
Wireless charging is a form of charging that defies the norm we are used to. It is an easy and convenient way to charge our devices. Usually, there are two requirements for wireless charging to work;
- A charger, in the form of a mat, a puck, or a stand, that is connected to a power source.
- An electronic device that is equipped with wireless charging abilities.
The technology underlying wireless charging is known as inductive charging, and we will discuss all these in the ensuing paragraph.
Firstly, we need to understand that the output of charging is measured in amperage and voltage. Voltage is representative of the strength of the current flowing through the circuit while the current tells us how much electricity is flowing. The product of the amperage and the voltage gives us power.
Now that we have cleared that, we can go on to the concept of normal charging and fast charging. Usually, a standard port for charging produces an output of 5 volts and 1 Ampere. However, most phones can still deal with current up to 2.4 Amps.
Fast charging, however, increases the current to 3 Amps and 9 or 12 volts. There are several methods of fast charging; the Qualcomm Quick Charge, and the Samsung Adaptive Fast Charging being the most common. However, there are others like the PowerIQ, Huawei SuperCharge, and OnePlus Dash Charging.
As we have earlier demonstrated, charging involves the gaining and loss of an electron. There are two simple ways by which we can do this;
- Charging by contact and
- Charging by induction.
We know you’re itching to hear all about both methods, we shall start with charging by contact.
In this case, the contact of a charged object is brought towards a neutral object and then, charges move accordingly. For instance, if a positively charged aluminum plate is brought towards a neutral sphere, the metal sphere is being charged that way, and this is solely due to the concept of charging.
Unlike the case of induction where the neutral object is brought close to the metal charging, charging by contact ensures that once a physical connection is initiated, charging ensues.
Let’s make it easier for you to follow; summarizing the principles of charging by contact.
What are the Principles of Charging by Contact?
When charged objects come in contact with a neutral object, they both have the same charge.
If two charged objects come in contact, the total charge of the system is preserved. This implies that the total charge is shared based on the capacity of each object.
If the objects come in contact with spheres, the total charge is contributed according to their radii, and this means that the capacity is directly proportional to their radius. Also, the implication is that if the spheres are equal, they have the same measure of charge.
Just like the name implies, charging by induction is a concept that allows the transfer of energy without the object touching another object. In this process, the metal objects are placed on insulating stands. When a charge is applied, the electrons move from one sphere to another, and then this causes polarization.
The spheres are then separated via the insulating stand, and the spheres have opposite charges on them. If there are any excess charges in the system,it is distributed evenly over the surface of the sphere. This is a simple illustration of how charging by electron works.
The conventional battery in use for most devices today is the lithium-ion battery, and the technology has soared in leaps and bounds since its inception. The battery requires a constant current, constant voltage (CCCV) algorithm for charging.
This means that the battery is charged with the current set to a certain level, usually 1 or 1.5 A. This is done until the battery reaches the desired voltage level. The concept of circuit accuracy and current limit comes into play when we consider how challenging it can be to reach the battery’s full capacity without overcharging or undercharging.
The margins for error are little, for instance, overcharging by just 1% can lead to 1% battery failure. Similarly, undercharging by 1% is likely to cause a drastic reduction in capacity.
Hence, how do we ensure that accuracy is achieved in spite of all these? Well, the controller is usually equipped with a precision voltage reference, an amplifier, and a resistance divider.
3、Electric Vehicle Charge Controller and Concentrator
Understanding the basics of charging and electric vehicles is a key step, but now we take it up a notch with charge controllers and charge concentrators. So, what does it do?
A charge controller limits the rate at which electric current is drawn from or sent to the battery. Applying it to electric vehicles, it means that an electric vehicle charge controller is a device that ensures that the battery of such a car is protected from overcharging, overvoltage, or deep discharging. Having an efficient charge controller will ensure that battery performance is not reduced and that the lifespan is lengthened.
A good charge controller is also key to ensuring that the battery doesn’t get completely drained out or discharged. This is done via controlled discharges; a technique that protects the life of the battery.
Usually, charge controllers are sold separately as another device in conjunction with a battery storage system. These charge controllers can disable the flow of current into the terminals of a battery once it is fully charged. The excess energy can also be diverted to another load.
An integrated chip can comprise several electrical components in a bid to carry out the same charge controlling ability in a larger energy storage system.
A charging pile is equipped with an intelligent controller that is tasked with measuring, controlling, and protecting the charging pile. Hence, for things such as monitoring the state, checking the fault condition, and the linkage control of the charging process, the charging pile will prove sufficient.
The charging pile has consummate protection functions, and these include protection from overcharging and undercharging. Also, the charging pile has short circuit protection, protection from overcurrent, leakage protection, earthing systems, and overtemperature protection.
The charging pile should be built to be compatible with the international standard models of different electric vehicles available on the market.
Charging piles are categorized according to some factors. These different classifications are discussed below.
Based on this classification, there are two types;
- Vertical charging pile and
- Wall charging pile
Vertical charging pile applies to outdoor parking spaces and parking spaces in residential apartments. However, wall charging piles are on the walls, making them ideal only for indoor and underground parking spaces.
Charging piles can either be public, special or self-use. Public charging piles are the ones provided by public agencies. Some of these types of charging piles are found in public car parks. Special charging piles are ideal for businesses, and they usually serve both the consumers of the company and the employees.
For an indoor charging pile, the protection is at least IP32. The free charging should also be able to withstand harsh atmospheric conditions, and there is also the need for better insulation and lighting conditions. With this in mind, the minimum protection level is pegged at IP54, and this protects the body, charging equipment, and personal safety.
Classifying based on the number of charging piles could either be a pile of one charge or more than one charge. With the level of modernization and electrification, multi-charging piles are becoming more common and electric vehicle charging via piles with more than one charge will speed up the charge and also save the labor.
We also have charging piles that either work with direct current (DC) or alternating current (AC). AC is usually minimal current with a very small pile. The installation is also very flexible and can charge to full capacity in 6 to 8 hours. If you have a charging pile in your home, it is most likely an AC charging pile.
For a DC charging pile, the current is higher, and then it also takes a shorter time to charge. Also, the charging pile takes up a considerably large area. Think of cases like electric buses, hybrid buses, electric cars, and commercial taxis.
For a charge pile of electric vehicles to measure up to the expected standard, certain requirements are in order. These requirements are delineated below.
1.The charging pile should support the display of local information that can actualize the setting of different parameters using input devices like the keyboard or the touchscreen. Also, it is expected that the user will input the charging time and the power required to charge in the system.
2.While the parameters outlined above are being set, the user should be able to begin the process of charging.
3.The charging mode should be selected from the display screen, and this same screen should display the status (the level of charging), the billing query, the charging card consumption, etc.
4.For the charging pile, a control system with the ability to control the charger per the specifications isgiven by the user. Also, the system should be able to print the documents detailing the consumed energy after charging.
5.The parameters of the vehicle being charged such as the voltage, capacity, the temperature, and the current, can all be monitored in real-time.
In a charging pile, ensuring the safety of the personnel and the cars is an utmost consideration. Here are ways by which safety is adhered to.
1.Personal protective equipment should be provided to prevent contact with highly corrosive battery cells.
2.A spill kit that aptly neutralizes the acidic mixture when an electrolyte spills out of the battery is also required.
3.Ventilation Systems that enables an improved air quality is a must. Remember that the charging process creates hydrogen atoms, and these can lead to dangerous concentrations if not properly handled.
4.Clear Signs and Labels for safety equipment and other devices that are potentially hazardous.
In the design and development of an electric vehicle charging pile, there are four core components required for the setup.
1.A system to detect the battery of the electric vehicle. Using either 50 Hz or 60 Hz, the electric bus runs on 580 – 600 VAC power. While the DC voltage is either 70V, 220V, 251 V, 336V, or 384V, with several possible combinations of battery packs in parallel and series, the capacity of the electric vehicle is one can take any of several possible outcomes, hence, a system that detects the actual number of batteries in use should be present.
2.A communication system to establish control and ensure the transfer of information. It is important that information isn’t lost. The communication interface should ensure the reliability of data under high load rate.
3.Information Recording and Credit Card Processing. For charging piles that aren't free, a pre-charging method is utilized, and the degree of each charge is based on the payment made.
5、Charging High-Tech PCB Board
The PCBs used for charging usually consist of a four-layered board of copper, with the appropriate thickness level. Remember that the thickness of the circuit usually dictates the level of voltage it can accommodate and the charging pile operates on a considerably high amount of voltage.
So, usually, the commonly used PCB is Tg150 and above, as high as Tg170. This high Tg refers to the heat resistance, and for PCBs underpinning high performance, high multilayer characteristics, higher heat resistance is required to ensure that the product is reliable.
In essence, if the Tg of a PCB is increased, this causes the material to have improved heat resistance, moisture resistance, and chemical resistance characteristics. Also, PCBs with high resistance to heat will demonstrate improved properties regarding mechanical strength, thermal decomposition, adhesiveness, dimensional stability, and water absorption.
According to forecasts, the number of electric vehicles on the road all around the world will increase from 3 million to 125 million in the next 12 years. Up till 2017, the global EV fleet has increased by 54% to about 3 million. One major factor that has spurred this growth is the emerging government policies and regulations advocating clean energy and sustainability.
There's no better time to invest in a safe, reliable, and efficient technology underlying components that go into the production of electric vehicles and the charging stations. As you know, safety is one of the most important considerations, and it is one factor that you cannot afford to compromise on.
We are skilled professionals with years of experience servicing a plethora of clients and meeting their PCB needs. Contact us today for your top-notch PCB manufacturing needs.