What is first aid and emergency treatment in pure electric cars?

1. First Aid
When rescuing an injured person in an electric shock accident, your own safety is the first priority. Never touch anyone who is still in contact with the voltage. If possible, immediately de-energize the electrical system, or use a non-conductive dry plank, broom handle, etc. to isolate the accident victim or electrical conductors from the voltage.

(1) Quickly disconnect from the power supply
After the body is electrocuted, it may be due to convulsions or loss of consciousness and other reasons, grasping the charged body, unable to get rid of the power source by itself. The first step in rescuing an electrocuted person is to disconnect the electrocuted person from the power source as soon as possible. The way to disconnect the power supply in an electric car is to wear insulating gloves to disconnect the electric shock person or cut off the high-voltage power supply. In short, it is necessary to adapt measures to local conditions and flexibly use various methods to quickly cut off the power supply to prevent the accident from expanding.

(2) On-site first aid
When the electric shock person is disconnected from the power supply, symptomatic rescue should be given quickly according to the specific situation of the electric shock person, and strive to be treated within 1 minute after the electric shock. Some data show that more than 90% of people who are treated within 1 min after electric shock have good results, and those who start treatment after more than 12 minutes have basically no possibility of life-saving. The main methods of on-site first aid are mouth-to-mouth artificial respiration and artificial chest compressions, and cardiac injection is strictly prohibited.
Mouth-to-mouth artificial respiration is an artificial method to replace the breathing activity of the lungs, so that air enters and exits the lungs rhythmically, supplying enough oxygen in the body, fully expelling carbon dioxide, and maintaining normal ventilation function.
Artificial chest compression method refers to rhythmically pressing the heart, replacing the natural contraction of the heart with artificial methods, so that the visceral function is restored and the blood circulation is maintained.

(3) First aid methods
① electric shock accident. Electric shocks generally have the following four symptoms, which can be given correct symptomatic treatment.
a. The mind is still clear, but the heart is flustered and the limbs are numb. For such persons, it is generally only necessary to take them to a cool and ventilated place to rest and let them recover naturally. But it is necessary to send someone to take care of it, because some patients may develop lesions after a few hours.
b. There is a heartbeat, but breathing stops or is very weak. Such persons should use mouth-to-mouth artificial respiration for first aid.
c. Breathing, but heartbeat stopped or very weak. In such persons, manual chest compressions should be used to restore their heartbeat.
d. Those whose heartbeat and breathing have stopped. This type of person is the most dangerous and the most difficult to rescue. First aid should be given with both artificial respiration and artificial chest compressions (ie, CPR). It is best to rescue two people together. If there is only one person to rescue, you should blow air 2 to 3 times first, then press the heart 15 times, and so on.
②Battery accident. In the event of a battery accident, the following requirements should be followed.
a. If the battery leakage, etc. comes into contact with the skin, rinse with plenty of water.
b. If you inhale the harmful gas from the battery, you must immediately breathe a lot of fresh air.
c. If the eyes come into contact with battery leakage, etc., rinse with plenty of water (at least 10 minutes).
d. If you swallow the dissolved substance in the battery, drink a lot of water and do not force vomiting.

2. Emergency treatment
The common emergency treatment needs of electric cars are as follows.
①Rescue: When the electric car is hit or the occupants need to be rescued.
②Fire: When an electric car catches fire, it should be treated as an “electric fire” and put out with a dry powder fire extinguisher.
③Leakage: When the high-voltage power battery fluid overflows, special measures should be taken.
④ Towing cars: deal with the situation of electric cars breaking down on the road.
⑤ Jump start: When the car cannot be started due to 12V power failure, use this method to start the car in an emergency.

(1) Rescue
When rescuing a high-voltage car, do not mistake the car for being in a shutdown state because it is relatively quiet. For hybrid cars , when the car is in “READY” mode (the Y light is on), the engine will automatically stop, so when checking or repairing the engine compartment, first check to see if the “READY” indicator has gone out.
Before handling the maintenance car, first block the wheels with blocks and apply the parking brake, engage the “P” block and confirm that the “P” block indicator light is on, then press the “POWER” button and confirm that the “READY” indicator light is off, disconnect the 12V auxiliary battery, and finally unplug the maintenance switch or HV fuse.
It should be noted that when working on electric cars, the emergency team needs to know that the orange cable represents high voltage. And wait for 5 minutes before disconnecting the high-voltage battery and contacting the cable, that is, when the capacitor is fully discharged.
In addition, if the high-voltage cable is broken during rescue, the system will automatically cut off the high-voltage power, because the insulation monitoring function on the car will continuously monitor the leakage of the high-voltage cable to the metal chassis. In addition, in the event of a crash, the airbag is deployed, and the high-voltage power supply will be automatically cut off. Even if the airbag does not deploy, if the deceleration sensor in the converter exceeds its limit, the high-voltage power will be cut off.

(2) Fire
The high-voltage power battery electrolyte is mainly composed of corrosive chemical liquids, so after a fire, a large amount of water or dry powder fire extinguisher can be used.
Conventional ABC dry powder fire extinguisher, suitable for oil or circuit fire fighting. However, if only the high-voltage power battery is on fire, a carbon dioxide fire extinguisher is recommended, and in the event of a large-scale fire or a large fire, continuous watering can also be used to extinguish the high-voltage power battery fire. But using a small amount of water, such as just a bucket of water, is dangerous and will actually exacerbate the magnitude of a high-voltage battery fire.

(3) Leakage
When facing the electrolyte that may be spilled from the high-voltage power battery, put on appropriate protective equipment as soon as possible, and use red litmus paper to check the spilled liquid. If the test paper turns blue, the spilled liquid needs to be carried out with boric acid solution. and. After the neutralization is complete, use the test strip to check the spillage to confirm that the color of the test strip has not changed. After neutralization, use a sufficient absorbent towel or cloth to absorb the electrolyte spilled in the accident.

(4) Towing car
When electric cars are towed, since most cars are front-wheel drive, the towing of such cars must strictly comply with the manufacturer’s requirements, otherwise the three-phase drive motor or transmission unit of the car may be damaged.
Whether it is a hybrid car or a pure electric car, the correct towing method is to make it all flat on the van, and then transport it to the designated location by the towing car. However, if it is a front-wheel-drive car , the car can also be towed with the front wheels off the ground.

(5) Jump start
Whether it is a pure electric car or a hybrid car, the power supply of the whole car control module is completed by a 12V battery. That is to say, in electric cars, in addition to high-voltage power batteries, all cars will be equipped with 12V low-voltage batteries.
The 12V battery is used to power all ECUs. Without this power supply, the ECUs cannot work and the car cannot be driven. If a pure electric car or hybrid car cannot be started, the 12V auxiliary battery can be jump-started.