On February 28, 2023, Redmi officially released the 300W Celestial Second Charge, regaining the top spot in mobile phone fast charge power. Most mobile phone brands will operate on multiple lines of main brands and sub brands. The main brand will be relatively "conservative" in terms of fast charging performance due to the need to take into account the overall balance, so the power race will be entrusted to the sub brands.
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285699.jpg?x-oss-process=style/cdt800w)
First of all, there must be a name. Friendly merchants have super flash charges, full level second charges, and super fast charges. Redmi calls them immortal second charges. October 2021, Redmi Note 11 Pro+released 120W immortal second charge, and in October 2022, Redmi Note 10 Exploration Edition released 210W immortal second charge. This time, the immortal second charge was upgraded again, and 300W immortal second charge was born.
Mobile phone charging enters the 5-minute era
The Redmi 300W Immortal Second Charge is installed on the Note 12 Pro+Magic Modification. Although it is an engineering prototype, it seems that the completion has reached the available status.
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285680.jpg?x-oss-process=style/cdt800w)
It can be seen from the AC power meter at the input end of the charger that the maximum power is 290W. It is speculated that the power of the cell phone battery is about 260W.
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285760.jpg?x-oss-process=style/cdt800w)
In order to more intuitively show how powerful the Redmi 300W immortal second charge is, the charging head network draws the AC power curve and the UI power percentage into a table. It can be seen that the platform with high power peak charging above 200W lasts for more than 2 minutes, which is extremely rare in many hundred watt high power mobile phones.
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285840.jpg?x-oss-process=style/cdt800w)
Now let's take a look at the charging speed. It takes only 2 minutes to charge to 44%, 3 minutes to charge to 70%, and 5 minutes to fully charge 100%, making the mobile phone charging speed officially enter the era of 5 minutes. If we look at the peak power stability interval time instead of the earlier power climbing phase, 27% of the power will be charged in one minute at the earliest.
300W fast charging architecture
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285961.jpg?x-oss-process=style/cdt800w)
In 2021, Xiaomi customized a 6:1 charge pump chip to solve the more complex problem of efficient multi-stage voltage division, and realized 67W wireless flash charging on Xiaomi 11 Pro.
Today, The Redmi 300W Immortal Second Charge also adopts a customized charge pump scheme. The customized 6:2 charge pump chip directly charges the battery core through multiple charge pumps in parallel, with a maximum conversion efficiency of 98%. Compared with the all available 4:2 charge pump chip scheme, the 6:2 charge pump chip has a higher voltage sharing ratio, which reduces the high current heating problem in the power supply path.
According to the above discussion, the super power charging uses the dual cell series connection scheme. The battery pack voltage is 8.9V, and the input voltage should be 26.7V when the 6:2 charge pump voltage is divided. It is speculated that the 300W immortal second charging voltage specification may be 30V10A or 28V11A.
15C ultra-high rate hard carbon graphite mixed negative electrode battery
After solving the problem of power supply channel, the pressure comes to the battery. The traditional high rate battery is generally only 5C-10C, which has met the bottleneck. Redmi 300W Fairy Second Charge introduced a new hard carbon material into the negative electrode of the battery to produce a hard carbon+graphite mixed negative electrode. The structure of the hard carbon material is more loose, which can allow lithium ions to be embedded more quickly during the charging process. In combination with the ultra-high conductivity electrolyte, the 15C high magnification cell was finally created, and the capacity also reached the usable level of 4100mAh.
Fourth generation dual GaN charger
![Redmi发布300W神仙秒充,6:2电荷泵硬碳电池等黑科技,实现5分钟充满-充电头网](https://chongdiantou-images.oss-cn-shenzhen.aliyuncs.com/wp-content/uploads/2023/02/2023022806285929.jpg?x-oss-process=style/cdt800w)
The 300W charger of the Redmi 300W Fairy second charger has also been upgraded synchronously. The fourth generation dual gallium nitride scheme is adopted. The flat transformer is upgraded to an integrated module design, and the gel filling process and large area graphene dual cooling assistance are added, so that it can maintain the peak power output for a long time. The 300W charger has the same volume as the previous generation 210W charger. The size of the previous generation of 210W charger is 67.4 * 64.69 * 29.79mm, the volume is about 129.89cm ³, and the power density is about 1.62W/cm ³. The power density of this generation of 300W charger has increased to an amazing 2.3W/cm ³.
Summary of charging head network
In the mobile phone market with fast charging performance, Redmi has played a good role as the goalie and shooter in the power competition. The Immortal Second Charge has soared from 120W to 210W to 300W. Finally, this generation of Redmi 300W Immortal Second Charge has achieved an amazing speed of 100% charging in 5 minutes. Charging fast to a certain extent has been an experience of "insensitivity". You can fill it without thinking about it, and completely forget that charging requires "time consuming" This matter.
The Redmi 300W Fairy Second Charge is full of black technology everywhere. The 6:2 custom charge pump chip is used in the power supply path. The 15C ultra-high magnification hard carbon graphite mixed negative battery is used on the cell. The power density of the fourth generation dual GaN charger has reached 2.3W/cm ³. Any point is a technical progress that can be discussed at length.
At present, the 300W Immortal Seconds Charge is still displayed as a prototype of the Magic Change, but it is believed that its various technologies will gradually be mass produced and applied to the main models and even the long-distance models, and we look forward to such a day coming as soon as possible.