In order to further lay a good foundation for the safety of electric bicycles, relevant national departments have successively issued a variety of policies and issued GB 17761-2018 "Safety Technical Specifications for Electric Bicycles", GB 42295-2022 "Electrical Safety Requirements for Electric Bicycles", and GB 42296-2022 "Safety Technical Requirements for Chargers for Electric Bicycles" and a series of national mandatory standards.
On April 25, 2024, the Ministry of Industry and Information Technology organized and completed the preparation of the No. 1 modification list (draft for comments) of the mandatory national standard "Safety Technical Requirements for Chargers for Electric Bicycles", refining and improving the existing standards.
As can be seen on the official website of the Ministry of Industry and Information Technology, opinions on the No. 1 modification list (draft for comments) of the mandatory national standard of "Safety Technical Requirements for Chargers for Electric Bicycles" are currently being openly solicited from the public.
As shown in the figure, there are two biggest changes in the new regulations, namely the prohibition of on-board chargers and the use of high-temperature coded identification plates for chargers.
What is an on-board charger?
During the investigation, the charging head network found that some consumers mistakenly thought that the ban on car chargers was a USB charger that prohibits the charging of mobile phones in the car after seeing the new regulations, which is a wrong understanding. Correctly, the new regulations prohibit the integration of "lithium battery/lead-acid battery chargers for e-bikes" into the body of the vehicle.
At present, some manufacturers on the market directly integrate the charger of electric bicycles into the body of the car, in order to solve the problems of charger carrying, storage, waterproofing, loss, etc., and even use this as a selling point for publicity. In addition to the manufacturer's behavior, Xiaobian also found that some users disassembled the charger and installed it in the car body without permission.
To add that, the average user temporarily placing an external charger in the storage compartment will not be considered a built-in car charger.
Why does the new regulation ban car chargers?
Taking a 48V electric bicycle as an example, if the charger is external, the 220V AC power from the wall socket is converted into 48V DC after entering the charger, and then transmitted to the charging port of the electric bicycle through the cable, 48V is a low-voltage DC current, which is not harmful to the human body. Even if the charger catches fire and explodes, the external solution will not affect the electric bicycle and will not cause the thermal runaway reaction of the lithium battery pack.
On the other hand, look at the built-in car charger, the charger is integrated into the car body, the 220V cable is inserted into the car body charger port, and all the conversion and transmission are completed in the car body. On the other hand, if the built-in charger catches fire and explodes, there is a great chance that the entire electric bicycle will be ignited, and the lithium battery pack will also explode in thermal runaway, so the built-in on-board charger is a serious safety hazard and should be prohibited.
The charger has a new code, and a permanent identification plate is also used
In addition to prohibiting built-in chargers, the new regulations also add a "code" item, which stipulates that all e-bike chargers must have a code consisting of a 13-digit code, which consists of the manufacturer code, the year of production code, and the model specification code.
In addition, the new regulations also require that the code should be engraved on the high-temperature resistance label, and the high-temperature test should be carried out in a heating furnace at 950°C for half an hour, and the coding information should be complete and clear at the end of the test. After the high-temperature resistant identification plate suffers from a fire and explosion accident, the relevant departments can trace the source according to the charger identification plate, and even carry out a series of operations such as accountability and recall according to the situation.
The electric bicycles on sale in Continental have fully adopted the new national standard charging interface
A few years ago, various electric bicycle companies developed their own charging interfaces and chargers for electric bicycles, which have different forms and different voltages and are not common to each other, and even plugs of the same form will have dangerous accidents because of opposite polarity. Non-universal plugs and chargers will cause waste of resources and pose safety risks. The picture above shows the charging interface of electric bicycles that once appeared on the market, which has been completely eliminated.
On December 29, 2022, the national mandatory standard GB 42296-2022 "Safety Technical Requirements for Chargers for Electric Bicycles" was officially released, unifying the interface standards.
GB 42296-2022 is officially implemented on July 1, 2023, and for products shipped or imported before the implementation date of this document, it will be implemented from the 13th month of the implementation date of this document. In other words, if an electric bicycle with a non-new national standard charging interface has a factory date of June 30, 2023, then its latest legal sales date is July 30, 2024. After the release of the new national standard, major manufacturers have successively cleaned up the inventory models of the interface, and the new production models have fully adopted the new national standard charging interface.
The new national standard interface is unified into two forms: lithium battery and lead-acid battery
The power source of the electric bicycle mainly depends on two types of batteries, namely lithium-ion batteries and lead-acid batteries, and the voltages and charging algorithms of the two batteries are completely different, so the charging interface is also designed with two plug forms: lithium-ion batteries and lead-acid batteries, which are not physically universal to avoid misuse.
The lead-acid battery plug is in the form of two power pins and two communication pins (2+2), while the lithium-ion battery is in the form of two power pins and four communication pins (2+4).
Now let's take the lithium battery charging plug as an example. The new national standard lithium battery charger socket (female) pin can be seen to adopt the "partition" design, the top four circular jacks are used to communicate with the charger for handshake, and the positive and negative poles used to transmit current are designed with thick horizontal bars, in which the positive electrode is an independent cavity, even if a child is inserted with metal objects such as screwdrivers and keys, the positive electrode of the independent cavity will not cause a short circuit. The negative electrode is wrapped with a communication needle.
The new national standard lithium battery charger plug (male) has a square appearance as a whole, the positive pole marked with the "+" symbol is in an independent cavity in the lower right corner, the negative electrode and the four communication pins are also placed in a large cavity, and the plug design of the positive electrode is physically isolated, which has the same ability to prevent short circuits caused by foreign objects by mistake.
The new national standard charger is mandatory to use the communication protocol, first shake hands and then charge
In addition to the unification of the charging interface, the new national standard charging plug for electric bicycles abandons the old fool-type direct power supply method, and compulsorily adopts the "communication protocol" method for charging.
"Safety Technical Requirements for Chargers for Electric Bicycles" refers to the practice of unified physical interfaces and different unified modes between mobile phones and new energy vehicles, and the charger and battery can only officially start charging after successfully shaking hands and asking for the correct voltage, so as to eliminate potential safety hazards due to mismatch. The new national standard charger and battery pack cable for electric bicycles will no longer have only two power transmission cores, but on the basis of the original power transmission core, a special signal transmission core will be added for the communication protocol between the charger and the battery pack.
Article 5.5.5 of the "Output Interface Security" item in the "Safety Technical Requirements for Chargers for Electric Bicycles" stipulates that the charger and the recharged battery pack (system) shall have a mutual recognition and coordination agreement. The lithium-ion battery charger or other battery pack charger should first be mutually recognized and coordinated with the rechargeable battery pack (system) to confirm the technical parameters of the battery pack before starting charging.
In this provision, after the charger plug is inserted into the charging jack of the electric bicycle, the communication core first tries to communicate and shake hands, and after it is successful, the charger will start charging. Even in the event of extreme misinsertion, the protocol cannot shake hands and will not be charged, eliminating potential safety hazards.
Summary of the charging head network
The release of the new national standard for electric bicycles has made the market more standardized, unified the charger interface standards, and completely eliminated the misuse of chargers from the physical and communication protocols. The new national standard for electric bicycles is constantly improving with the market, and the draft has been revised to the "Safety Technical Requirements for Chargers for Electric Bicycles", the two biggest points are the prohibition of on-board chargers and the addition of permanent high-temperature resistant signs.
It is forbidden to integrate the charger into the car body, which can avoid 220V AC directly entering the car body and causing electric shock accidents, and greatly reduce the possibility of charger failure causing the whole vehicle to burn. The charger has added a high-temperature coded identification plate, and it can be traced according to the identification plate in the event of a fire and combustion accident, which is believed to promote charger companies to improve the quality and safety of products.
Under the guidance of the new national standard, the safety of the latest electric bicycles on the market has far exceeded the old models of a few years ago.
Related Reading:
1. The "Safety Technical Requirements for Chargers for Electric Bicycles" will be officially implemented on July 1
2. The new national standard plug for electric bicycles has been supplied and will be replaced on a large scale
3. The new national standard charging plug for electric bicycles is exposed, which is common across brands and improves safety
4. Interpret the new national standard charging port of electric bicycles to join the communication protocol, and understand it in seconds after reading
5. CCTV reported that the quality of electric bicycle batteries was spot-checked by the country, and the failure rate was as high as 22%