Although a power bank is only made of a shell, battery cell, and circuit board, the manufacturing cost can differ. This is also the most fundamental factor that determines the quality and price of the power bank.
Battery Cell Cost
There are 2 types of batteries for power banks. One is 18650 cylindrical lithium batteries; the other one is polymer lithium batteries. Generally, the polymer one is better than 18650 lithium batteries in terms of safety performance. However, the cost is relatively high.
For 18650, the popular capacities are 2000mAh, 2200mAh, and 2600mAh. And there are different grades there: A, B, and C. The quality A battery is best with a 1-year warranty, while grade B and C batteries may be second-hand cells. The wholesale prices for grade A batteries are RMB8.5 for 2000mAh, RMB10.5 for 2200mAh, and RMB13.5 for 2600mAh.
As to the polymer cell, the capacity and size can be customized at will. The factory wholesale price is about RMB6.5 per 1000mAh. It means the cost is RMB32.5 if it is 5000mAh.
Now, most of the factories are using the polymer cell with RMB4 per 1000mAh. So the cost for a 10000mAh cell is RMB40. In addition to R & D, circuit board, shell, and other fees, the cost of a 10000mAh power bank is about RMB60 in the case of quality assurance. To take a step back, the price of RMB50 is almost to the limit even if the big factory has the upstream advantage. If a 10000mAh portable charger is less than RMB50, you’d better confirm the samples also with 1-2 trial orders firstly.
If you use 18650 lithium batteries to make a 10400mAh power bank, usually 4*2600mAh batteries are inside. The cost price is about RMB10 to RMB14 per cell according to the quantity, then 4 Lithium batteries cost RMB40 to RMB56.
Circuit Board Cost
An excellent PCB circuit board may cost tens of RMBs, while ordinary circuit boards often cost more than RMB10. A superb circuit board allows the mobile power supply to exert its maximum performance. Otherwise, accidents cannot be avoided even with high-quality batteries. A good circuit design can protect the battery cell, reduce loss and heat generation, ensure the energy high converting rate, and stabilize the current. Besides, high-quality mobile power circuit boards can protect the charging safety of mobile phones and other digital devices.
However, the PCB circuit board is easy to falsify as well. The cheap power bank with larger capacity usually uses poorly designed circuit boards. The scheme can be dealt with at the cost of less than RMB5.
Here are 2 types of PCB circuit boards on the market.
1. Direct-charge and direct-discharge circuit board: equivalent to a mobile phone charger, plug it in to charge and disconnect it to power off. The wholesale price is between RM8 and RMB10.
2.Intelligent protection circuit board: It has over-current, overload, over-charge, and over-discharge protection functions for mobile phones, and the wholesale price is between RMB12 and RMB15.
The safety, stability, and conversion efficiency are varied for different solutions of circuit boards. Although the low-priced ones can work, the quality is not as good as the high-priced circuit boards.
Most power bank cases are made of ABS+PC materials. The cost of a steamed bun-sized shell costs between RMB5 to RMB7 (additional RMB1 if with LED lights). Above, the shell is generally less than RMB10.
If the shell cost is more than RMB10, it is with the second-oxidized aluminum alloy or other more expensive materials.
Built-in Cable Cost
At present, a USB cable with 8 plugs is the mainstream on the market. The wholesale price is between RMB4.5 and RMB6. And the packaging is between RMB1.5 and RMB2.5. Therefore, the total price of wire packaging is between RMB6 and RMB8.5.
Based on the fact that 4 workers assemble 1000 sets of portable power, plus wages, rent, water, and electricity, the processing cost should be between RMB1.50 yuan and RMB3.50 per unit.
After checking the overhead costs, we can see that a mobile power supply is not low. Coupled with the brand, it not only includes the product cost but also comes with the brand’s services. So it is the reason to choose the branded power bank. The purchase of a brand portable charger is the purchase of the product and includes the services.