Cells are the main component of a battery pack, which provide the primary power source. The voltage of a battery pack is the voltage of single cell multiplied by the series cells’ number and its capacity is the capacity of the individual chain multiplied by the number of parallel chains. For applications which require higher voltage and more capacity than a single cell can deliver, some custom battery packs are assembled with both series cells and parallel cells so that both the voltage and amp hour capacity are increased. We supply not only a wide range of standard cell models but also customized ones in order to best fit for customer's special requirements.
Lithium ion cells cannot be used directly in electronic devices. They need special protection and control circuits to keep them within their predefined voltage, current and temperature operating limits. They have to be assembled with a PCM (protection circuit module) and other components of different devices. PCM works as safety devices and it protects cells against over charge, over discharge, over current, short circuit and over heat. Sometimes more complex designs may use integrated PCM and BMS (battery management system) which provide advanced functions such as fuel gauge calculations, protection, cell balancing, thermal sensing, statues indicating lights and serial communications buses. BMS is mainly used in high power lithium ion batteries.
Mechanical design of a battery pack has to meet the requirements for physical and electrical interfaces with the appliance as well as maintain the assembly form and protect all the components. It involves the pack shaping, housing, insulation and external contacts. The simplest and low cost way is designing a shrink-wrap packaging and wire lead terminals with or without connectors. More complex is a typical injection molded plastic case and metal contacts for more precision packs. Either an external shrink-wrap or plastic enclosure, by applying 2D/3D systems and automation equipments, we are able to design cases and contacts with high precision and reliable connection.
A battery pack/module is a set of any number of identical batteries or individual cells. Its purpose is to provide an integrated powre source for applications. They may be configured in a series, parallel or a mixture of both to deliver the desired voltage, capacity, or power density. Components of battery packs include individual cells, management circuits and the interconnects which provide electrical conductivity between them. For an inline package, cells are selected and stacked with solder in between them. Cells are pressed together and a current pulse generates heat to solder them together and to weld all connections internal to the cell. With advanced equipments and a collection of professional R&D staffs, we can offer "one stop" services to OEM customs for their innovative products.
Lithium ion batteries must use "Constant Current /Constant Voltage (CC/CV)" charging method. First the battery is charged till it reaches a set voltage by using a set constant current and then charged with this constant voltage till the current is below 0.02C. Lithium ion batteries have charging voltage and current limits. If charged exceeding this limit, the batteries will be permanet damaged. Correct charging system also has effect on battery performance such as running time and cycle life. So the charge must be strictly controlled. In designing charging system special considerations are necessary to ensure the battery can be both fully charged but at the same time not overcharged. We use the world high precise circuit components to monitor and control the current and voltage statues.
With the industry leading technical knowledge and extensive exprerience we can provide complete power solutions, ranging from advanced cells, battery packs, managing system, charging to power supplies. We begin the design process by understanding customer’s performance targets for the final product. The first step in this process is to collect as much performance information as possible, including electrical characteristics, mechanical characteristics, enviroment conditions, testing and qualification etc. If you did not find one of our standard products that can meet all your requirements, simply fill the custom battery form. Our well experienced team can work closely with you to customize them to perfectly suit your particular needs.