We are not only sale lithium batteries, but also provide solutions for lithium battery applications. The key points of project design are: safety, durability, price and speed.
Regarding safety problem, we will describe it in SAFETY section right after the SOLUTION section, and will made a huge point about the speed in the third section SERVICE. Here we talk about durability and price first.
There are many factors which can influence durability, the major reasons are the quality of cell、PCM、electronic wire and connector, precise design of charge and discharge management, excellent process in production and the depth of consideration of the actually uses environment, etc. Then how can we control the quality when design the project?
1) The consistency of the cells must be good. It’s necessary to strictly match the cells’ group to ensure that the voltage difference between the cells is less than 5mV, the resistance difference is not greater than 5mΩ, and the capacity difference is not more than 20mAh; The discharge platform of the battery should be large. We try to use high discharge rate battery cells especially for devices which require large current to operation. We mainly use Panasonic, Sanyo, and Samsung cells, domestic Lifepo4 and Lithium polymer cells.
Strict cell matching
2) For PCM, which is also called BMS, We use the Seiko IC and AO MOS, other components must be genuine, too. PCM should be thickened and electric wires should be simple without cross. The layout of each soldering pad should be reasonable (a reasonable layout of soldering pad is good for shorten the length of the connection sheet to reduce the internal resistance and the hidden dangers when assembling battery packs), and the overall shape of the PCB board must be matched with the battery pack and customer’s request.
Classic case diagram
3) The electronic wire must be the Chinese standard UL1007. For the high current and high environmental temperature battery project, we must use silicone wires to ensure that the cable cover won’t break. The conductivity, current endurance ability, reasonable length and diameter of the electronic wire is not only affect the safety but also affect the internal resistance and voltage drop.
4) Connector, also known as terminal and plug, steady connection is good for charging and discharging, and it could effectively reduce the contact resistance. Different quality connector has big different performance in service life and fire, short-circuit prevention function, we can distinguish the quality even with the naked eye. For example, Tyco connector (Plug: 1969442-2, Container socket: 2110989-1), you can see the differences between the genuine and imitation goods below. According to the level of protection, we must make a reasonable choice for those connectors that are exposed to wet conditions or the natural environment. Such as the aviation plug、XLR connectors, etc.
5) Charge and discharge design. The charging mode of lithium battery is constant current-constant voltage; this requires that our charger must be designed in accordance with the pattern. Moreover, charging current and charging efficiency should also be considered. The charging current is too large or too small will not conducive to prolong the service life of the battery, a 0.2C standard charging current is the best choice. The charging efficiency is mainly reflected in the reliability of the charge cut-off voltage and the stability of the cut-off charging current, which are the keys to extend the battery life. As for how to achieve these standards, the selected components and programs are not the same in different cases, so we prefer to discuss it case by case.
6) Fabrication technology. Please refer to “Custom PK” in the “Custom online” section on the website
7) Deep thinking about the actual operating environment. It is impossible for us to make design after visiting each customer’s place. We often come up with the final solution through the customer's description based on our years experience. Such as tree branch scissors, when the tree branch scissors is working, the thickness and hardness of the branches will affect the motor even make it locked. This must be considered in the design to improve the discharge cut-off current and prevent countercurrent. Otherwise it will seriously damage the battery pack or even immediately stop working; Another example is the electric bicycle battery, extreme weather, rain and beat situation should be considered.
We have been pursuing cost-effective program since established the company. Under the premise of ensuring safety and quality, we have been committed to using the most economical solution to achieve the product and optimize the process. We are against profiteering and only make a reasonable profit. Once the customers choose us, they won’t change because of price reason. Price is never the reason that we can’t cooperate together. The balance between price and value won’t break, we have been insisting this for 10 year, never changed.
In order to make better solutions, thus to achieve better products and fair trade promise, we list 20 basic factors that affect the battery price as below:
1. Battery voltage: the higher, the more expensive.
2. Battery capacity: the higher, the more expensive
3. Battery size request is strict or not.
4. The length of electric wire: too long or too short is more expensive.
5. The model of electric wire: too small or too big is more expensive.
6. With or without connectors and it’s complexity.
7. The smaller battery cell, the higher cost for processing.
8. The assembling technology for battery packs.
9. Working current of the electric appliance: the larger the more expensive.
10. The higher degree of intelligent, the more expensive.
11. A new mould is needed or not.
12. Whether need to develop new frock clamps or not?
13. Packaging request
14. Whether need to provide certification/testing data or not?
15. Terms of payment.
16. Seasonal factors: peak season is expensive, off-season is cheap.
17. Order quantity.
18. The attitude and requirement about defective products.
19. Delivery time.
20. Trade procedure.