Electric vehicle (EV) batteries are categorized by voltage into 48 volts, 60 volts, 72 volts, and so on. Common capacities for lead-acid batteries include 12 ampere-hours (Ah), 20 Ah, 32 Ah, etc. Graphene batteries have a higher energy density, with common capacities being 14 Ah, 23 Ah, 38 Ah, etc. The term "Ah" on EV batteries typically refers to "ampere-hour (Ah)."

Many friends have inquired about the charging of electric vehicles, and here are the issues that have attracted more attention: How much electricity does it take to charge an electric vehicle battery once? How is the charging fee calculated at charging stations? Why are people reluctant to charge at charging stations? The following provides a detailed introduction.

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Calculation method for the amount of electricity needed to charge an EV battery: The amount of electricity required to charge an EV battery once can be calculated using the formula: battery voltage x battery capacity.

Calculation of the electricity required for charging various models of lead-acid batteries: According to the electricity calculation formula, the electricity required to charge a 48-volt 12 Ah and 20 Ah battery once is: 48 x 12 = 576 watts = 0.576 kWh, and 48 x 20 = 960 watts = 0.96 kWh.

According to the electricity calculation formula, the electricity required to charge a 60-volt 20 Ah and a 60-volt 32 Ah battery once is: 60 x 20 = 1200 watts = 1.2 kWh, and 60 x 32 = 1920 watts = 1.92 kWh.

According to the electricity calculation formula, the electricity required to charge a 72-volt 20 Ah and a 72-volt 32 Ah battery once is: 72 x 20 = 1440 watts = 1.44 kWh, and 72 x 32 = 2304 watts = 2.3 kWh.

Calculation of the electricity required for charging various models of graphene batteries: According to the electricity calculation formula, the electricity required to charge a 48-volt 14 Ah and 23 Ah battery once is: 48 x 14 = 672 watts = 0.672 kWh, and 48 x 23 = 1104 watts = 1.1 kWh.

According to the electricity calculation formula, the electricity required to charge a 60-volt 23 Ah and a 38 Ah battery once is: 60 x 23 = 1380 watts = 1.38 kWh, and 60 x 38 = 2280 watts = 2.28 kWh.Based on the electrical energy calculation formula, the required electricity for a 72-volt 23-ampere and 38-ampere battery to be fully charged is as follows: 72x23=1656 watts = 1.65 kWh, 72x38=2736 watts = 2.73 kWh.

The necessity of constructing charging piles: On April 15, 2019, the new national standard for electric vehicles was introduced. According to the regulations, a 48-volt electric vehicle is classified as an electric bicycle, and the total weight of the vehicle must not exceed 55 kilograms. This has resulted in the inability to continue using lead-acid batteries previously in use, and only lithium batteries with a weight one-third that of lead-acid batteries can be used.

The advantages of lithium batteries are high energy density, light weight, and long service life, while the disadvantage is that short circuits can cause thermal runaway, leading to combustion and fire. Many vehicle owners using lithium batteries live in residential areas and may park their electric vehicles in the overhead floors or charge them at home. Once a lithium battery catches fire, the hazard is immense.

The causes of lithium battery fires include overcharging, over-discharging, battery impact, unauthorized changes to the circuitry, and once the protection board fails, these four situations can all cause the battery to short circuit, leading to thermal runaway and combustion. In the early stages of a lithium battery fire, water and ordinary fire extinguishers, as well as sand and soil, are completely ineffective in extinguishing the fire.

Once a lithium battery catches fire and burns in an enclosed space, within a few seconds, temperatures of several hundred degrees Celsius accompanied by a large amount of thick smoke will destroy everything in the space. If the people on the scene inhale 3 to 5 breaths of toxic and harmful smoke, it will cause suffocation and death. If the fire is not controlled, it will spread to higher places, potentially causing a larger casualty incident, such as the fire in Nanjing, which resulted in 15 deaths and 44 injuries.

In order to ensure the safety of people's lives and property, the state has increased the management of electric vehicles. It is forbidden to bring electric vehicles into elevators, homes, or other public areas for parking and charging. The property management of residential areas actively builds parking spaces for electric vehicle owners and provides safe charging services. The charging places are also equipped with smoke alarm devices and fire-fighting equipment. This can effectively reduce the hazards brought by lithium battery fires.

The working principle of the charging pile:

1. The user pushes the electric vehicle to the vicinity of the charging pile, first connects the charging connector of the electric vehicle, and then connects the power source of the charging pile.2. After the power supply is connected, the system will automatically recognize the type and specifications of the battery. The type refers to lead-acid batteries or lithium batteries, and the specifications refer to the battery capacity, such as common 12Ah, 20Ah, 23Ah, 32Ah, 38Ah, etc.

3. Next, the system identifies the charger specifications, transfers the current to the charger, and the charger converts the 220-volt AC power through a transformer to a voltage and current suitable for battery charging requirements.

4. The charging pile can control the charging voltage, charging current, and charging time through the backend. The charging pile can detect the battery capacity and automatically and accurately control the charging time to prevent overcharging of the battery.

5. The charging pile is usually equipped with protection measures such as leakage protection and overload protection to ensure the charging process is safe and reliable.

6. When the battery is fully charged or the user-set charging time is reached, the charging pile will automatically stop charging (automatically cut off the power supply), and the charger will also stop working.

There are four billing methods for charging piles:

1. Most communities use time as the billing method, for example, pay for 3 hours if you charge for 3 hours, and pay for 8 hours if you charge for 8 hours.

2. Different charging piles have different billing methods. Some communities charge based on the actual electricity consumption on the charging pile, which is the most popular billing method.

3. Some community charging piles may offer charging package services. By purchasing a charging package at one time, it can be used within a certain time frame.4. Different charging methods at different time periods, for example, charging at night is relatively cheaper, while charging during the day is relatively more expensive.

Why are people reluctant to charge their electric vehicles at charging piles?

Nowadays, the management of electric vehicles has been intensified across the country. Property owners living in communities are prohibited by property management from pushing electric vehicles into the elevator or charging them at home. This can effectively prevent fire accidents caused by the explosion and combustion of lithium batteries, ensuring the personal safety and property of the owners.

Property companies have built dedicated parking areas for electric vehicles in relatively safe places in the community, providing safe charging services. This can avoid the trouble of car owners frequently pushing their electric vehicles around, and also reduce safety hazards brought by fire. This is very convenient for the owners, so why are many electric vehicle owners reluctant to charge at the charging piles?

In fact, the reason is very simple. Most of the charging piles on the roadside or in the community charge by time, averaging 0.6 yuan per hour. Taking a 60-volt 32-ampere battery as an example, it takes 10 hours to fully charge, and it costs 6 yuan for a single charge. A 60-volt 32-ampere electric vehicle needs 1.92 kilowatt-hours of electricity for a single charge. If charged at home at a rate of 0.6 yuan per kilowatt-hour, it only costs 1.2 yuan for electricity. However, charging 1.92 kilowatt-hours of electricity at a charging pile costs 6 yuan, averaging 3.12 yuan per kilowatt-hour, which is even more expensive than the cost of charging an electric car at a charging pile, and it is a huge profit.

If we extend the time, still taking a 60-volt 32-ampere electric vehicle as an example, charging once every three days, 10 times a month, and 120 times a year, the cost is 720 yuan. If charged at home, it is also once every three days, 10 times a month, and 120 times a year, the cost is only 144 yuan, saving 576 yuan compared to charging at the charging pile. In fact, this amount of money is not much for people with higher income levels now, but everyone is reluctant to be overcharged.

Why are the costs of charging piles so expensive?

In fact, some charging piles in the community and on the roadside are not laid out by the state grid, but are jointly built by local private enterprises and property companies, which belong to investment and business operations pursuing profits. Charging electric vehicles at charging piles is charged by time, and the charging voltage and current parameters can be changed in the background to extend the charging time.For example, the common battery capacities for 60-volt electric vehicles are 20 ampere-hours (Ah) and 32 Ah. When charging, the charger outputs a voltage of 74 volts and a current of 2.8 amperes (A) and 3 A. Assuming that your battery still has half of its charge, using the normal charging current and voltage, it takes approximately 4 hours to fully charge a 20 Ah battery, and about 6 hours for a 32 Ah battery.

Property management companies can reduce the charging voltage and current in the background to extend the charging time, thereby increasing the charging fee. Charging an electric vehicle at charging piles on the roadside or in the community costs much more than the actual electricity consumption fee.

I want to say that charging piles are meant to serve the general public. It's acceptable to make a profit, but not at the expense of exorbitant profits. With the increasing management of electric vehicles across the country, it is prohibited to push electric vehicles into the stairs or home for parking and power outage, and to charge with "flying wires." The high charging fees at charging piles bring inconvenience to users of electric vehicles, and may even lead to a situation where there is "no electricity to charge."

This requires relevant departments to manage and restrain this phenomenon. The investors of charging piles can make money, but not at the expense of exorbitant profits. The practice of charging based on time should be abolished, and charging should be based on actual electricity consumption. Only by doing so can the charging fees be open, transparent, and reasonable, allowing more car owners to charge at public charging piles. Otherwise, many car owners may secretly push their electric vehicles home or charge with "flying wires," increasing the safety hazards of fire.

Summary:

Electric vehicles are divided into 48V, 60V, 72V, 84V, 96V, etc., according to the battery voltage. To know the electricity consumption of a battery charge, use the formula: battery voltage × battery capacity. If you also want to know the electricity consumption of your electric vehicle each time it is charged, you can calculate it according to this formula. If you charge at a charging pile, the charging fee each time is different because the remaining battery charge is different each time.

Nowadays, the management of electric vehicles is becoming stricter. Pushing electric vehicles home for parking or charging is not only against regulations but also poses safety hazards. In this case, when the electric vehicle is "out of power," it can only be charged at a charging pile. However, the charging pile charges based on the charging time, which is quite expensive. This leads many users to be unwilling to charge at the charging pile, and they may secretly push their electric vehicles home for charging, increasing the probability of fire accidents.

The solution is for the investors of charging piles to consider issues from the actual needs of the public and reduce the charging fees. Change the charging fee based on time to actual electricity consumption, making the prices open and transparent, and profits can be made but not at the expense of exorbitant profits. In this way, more and more electric vehicle owners will charge at the charging piles, and the probability of fire accidents will also decrease. Do you think I'm right?