Domestic batteries have large capacities, but they can't be used in Samsung phones or iPhones.
When it comes to the Samsung Galaxy Z Fold7, which was just released last week, leaving aside its starting price of 13,999 yuan, two data points have generated the most buzz:
People applauded its 8.9mm thickness, while comments went wild about its 4400mAh battery.
Looking at Chinese domestic smartphone brands, a 6000mAh battery has almost become the standard for flagship models, and some phones are even catching up with the battery capacity of certain power banks.
However, when we look at Apple and Samsung, the two major brands that lead and define industry standards, they seem to be lagging behind in terms of charging and battery life. Eventually, it all boils down to one phrase:
You're a great phone, but unfortunately, you only have a 4400mAh battery.
Is the situation really that simple? Apple and Samsung together invest over $50 billion in R & D every year. Is it really just because they "don't want to use large-capacity batteries"?
— Of course not. Based on ifanr's research, we believe the situation regarding battery capacity in recent years is as follows:
The fierce parameter competition in the domestic market, high consumer expectations, and the successful implementation of advanced battery industry chain technologies have jointly contributed to the popularization of high-density, large-capacity batteries represented by silicon-carbon batteries in domestic smartphones.
However, in major international markets such as the United States, the battery capacity of mobile phones is capped at "20 watt-hours per single cell." Once this limit is exceeded, logistics and compliance costs will increase significantly. Therefore, most international versions of foreign brands and domestic brands can only stay below the 20 watt-hour limit.
Domestic brands, which mainly sell within the country, can afford the additional logistics and time costs associated with large-capacity batteries (such as having to use land transportation instead of air transportation).
Although silicon-carbon anode batteries can achieve extremely high energy density, their durability and safety still need to be verified over time.
New Battery Technologies in China
In the past year or so, battery technology in domestic smartphones has made great leaps forward. In the first half of this year alone, we witnessed the imaging flagships of Huawei, Xiaomi, OPPO, and VIVO all approaching or reaching 6000mAh, the battery capacity of small foldable phones crossing the 5000mAh threshold, and even mid - and low - end models starting to challenge the 7000mAh mark. They are practically power banks that can make calls.
Undoubtedly, domestic consumers this year are using the most powerful and highest - capacity smartphones in the world, outshining those in any other country.
Image | Xiaomi official website
The driving force behind this vibrant and competitive landscape is undoubtedly the rapidly advancing high - density silicon - carbon anode lithium - ion batteries. A battery industry report released by Tianfeng Securities at the beginning of this year pointed out:
The trend of adding silicon to mobile phone batteries is evident, with the proportion ranging from 5% to 10%, and it is not limited to high - end models. Since the beginning of this year, companies such as Huawei, VIVO, OPPO, Honor, OnePlus, and Xiaomi have all released phones using silicon - based anode material batteries, and the trend of moving from flagship models to mid - and low - end models is obvious, which will significantly increase the usage of silicon - carbon anodes.
Currently, the specific capacity of graphite anode lithium - ion batteries is approaching its theoretical limit. Silicon anodes can increase the theoretical upper limit from 372 mAh/g of graphite to nearly ten times, reaching 4200 mAh/g.
What does a ten - fold improvement in theoretical specific capacity mean?
It means a significant increase in the energy density of each battery cell. This improvement is crucial for small - sized electronic products like mobile phones. Moreover, these increased milliampere - hour figures can be translated into marketing data, which is even more important in the highly competitive domestic mobile phone market.
Image | IDC
Why Don't Foreigners Use China's Great Battery Technology?
Do you think Apple and Samsung, which invest billions in R & D every year, don't know the benefits of large - capacity batteries or lack the technology to produce them?
Obviously not.
Silicon - carbon batteries are not monopolized by Chinese companies. In fact, Japanese and Korean companies such as Shin - Etsu Chemical, 3DC Co., Ltd., SK Materials under the South Korean SK Group, and POSCO Silicon Solutions hold many technology patents related to silicon - carbon anodes and have considerable influence in the R & D and production processes:
The silicon - carbon anode material factory in Sangju, South Korea, jointly established by SK Materials and the US silicon - carbon material company Group14
So why don't we see large 5000 - 6000mAh batteries in iPhones and Galaxies?
Actually, what's holding Apple and Samsung back is the United Nations "Recommendations on the Transport of Dangerous Goods." More specifically, it's Special Provision 188 (UN Special Provision 188) within it.
This provision states:
1.
If the capacity of a single lithium - ion battery cell is less than 20 watt - hours, it is considered a "small battery" and can follow simplified and low - cost transportation rules.
2.
Once the capacity of a single cell exceeds 20 watt - hours, the battery will be classified as a "dangerous good" and must follow very strict packaging, labeling, declaration, and protective transportation specifications in international logistics, resulting in a significant increase in transportation costs.
From left to right: Lithium - ion battery cargo code UN3480, cargo type 9 "Other dangerous goods," can only be transported by cargo aircraft | Epec
Naturally, smartphones such as the iPhone, Samsung Galaxy, and international versions of domestic brands are most affected by this special provision.
For Apple and Samsung, which need to transport over 200 million phones globally each year, if they don't want their transportation costs to skyrocket, they must limit the total battery energy to less than 20 watt - hours.
In fact, that's exactly what they do.
Take the iPhone 16 Pro Max as an example. It uses a 4685 mAh battery with a nominal voltage of 3.88V, which is equivalent to 18.17 watt - hours.
Similarly, the total battery energy of the S25 Ultra is 18.84 watt - hours.
The 4400 mAh battery of the much - mocked Z Fold7 has a total energy of 17 watt - hours.
You should understand now that it's not that Apple and Samsung can't afford large - capacity batteries. It's that they need to consider markets outside China more than domestic manufacturers. To keep logistics costs under control and maintain profit margins for continuous R & D, they have to choose the small - battery route first.
The business world is tough, and Apple and Samsung want to make more money.
Of course, the reason why Apple and Samsung stick to the 20 watt - hour limit is not just the international dangerous goods transportation regulations. As large - scale global enterprises, from a business perspective, their product industrial design and procurement strategies tend to be conservative, which includes battery technology - especially Samsung, as it doesn't want to relive the nightmare of the Note 7 battery explosions...
In any case, if the international logistics safety regulations don't relax, there won't be a significant leap in the battery capacity of Apple and Samsung phones in the next year or two.
But here's an aside: Although the battery in the Samsung Z Fold7 is small, its performance is quite impressive. After 2000 charge - discharge cycles, its available capacity can still remain above 80% - far exceeding the 800 - cycle passing line set by the new EU regulations.
And the durability of batteries is exactly what the silicon - carbon anode battery technology, favored by Chinese manufacturers, still needs to be observed.
SM - F966B/DS is the European version of the Samsung Z Fold7. The 80% remaining capacity after 2000 cycles is shown in the bottom - left corner
The Current State of Silicon - Carbon Batteries: Just the "Present Reality"
Although silicon - carbon battery technology can currently achieve extremely high energy density, it also brings two major unsolved problems:
The physical expansion of the silicon anode and the shortened cycle life.
Silicon - carbon composite material used for the anode of lithium - ion batteries | Novarials
As previously mentioned in an ifanr article about power banks, currently, mainstream lithium - ion batteries use graphite as the anode material. Silicon - carbon batteries replace graphite with a silicon - containing carbon (graphite) composite material.
However, silicon undergoes significant volume expansion during the charging process. Although the expansion rate of the composite material is not as extreme as the 400% of a pure silicon anode, it is still much higher than the mere 10% expansion rate of graphite. The material fatigue problem caused by long - term repeated expansion and contraction cannot be ignored.
You don't want your phone to end up like this, right? | Tom's Guide
On the other hand, the silicon in the silicon - carbon composite material has higher chemical activity than graphite and is more likely to react with the electrolyte. This causes the "solid electrolyte interphase" on the anode surface to repeatedly break and re - form during charge - discharge cycles, accelerating the consumption of lithium ions and the electrolyte.
The macroscopic manifestation of this consumption is that the available capacity of silicon - carbon batteries decays faster.
For ordinary people, these two problems mean that although silicon - carbon batteries have high capacity and high power, your phone may display a "battery health alert" earlier, and the battery life may decline more significantly.
Therefore, although most domestic flagship models started using silicon - carbon batteries or similar technologies at the end of last year and the beginning of this year, the durability and lifespan of these batteries need time to be verified.
Of course, there are too many smartphones in the Chinese market, with a wide range of choices and relatively low replacement costs. That's why most domestic Android manufacturers only promise 300 - 500 charge - discharge cycles when advertising their phones. Chinese consumers may change their phones long before the battery fails.
Moreover, from a business operation perspective, the relatively high turnover rate and low battery replacement cost in the domestic market may be the only place in the world where a "consumption war" of silicon - carbon batteries can be waged.
So, the fact that Apple and Samsung haven't changed their battery capacity for so many years isn't just about being stingy. There are far more regulatory obstacles in the international transportation and cross - border sales of their products than we think, which are hard to notice when we only look at large - capacity domestic models.
Conversely, for domestic phone manufacturers, the challenges they face when going global are not limited to battery capacity.
Image | 36Kr
This article is from the WeChat official account "ifanr" (ID: ifanr), written by Ma Fuyao, and published by 36Kr with permission.