CNET in-depth analysis: Pay attention to six issues of smart phone battery

The evolution of the smart phone market has always revolved around the question: How do you arbitrarily access the applications and services that consumers like?

No smart phone manufacturer can give a satisfactory answer, because all manufacturers face a dilemma: higher performance electronic products, faster data transfer. The quality of video and games is better, the display is more vivid and refined, and its development rate follows Moore's Law, but the batteries used cannot meet the demand. It is an indisputable fact that smartphone users complain that battery life is too short.

The contradiction between functionality and battery life is the best interpretation of the older version of the new iPad design. Meet the needs of retina display, 4G LTE network, graphics processing improvement, battery size and weight need to increase by 70%. Even so, the new iPad battery life is still less than the iPad 2.

Smartphone manufacturers have been pushing designs that have been limited by lithium-ion batteries. If you want to learn about the future iPhone 5, Android device Windows Phone function, you need to first understand the six issues of smart phone battery:

1. Sealed battery packs Lithium-ion battery sealed packages containing layered anodes and cathode plates separated by separators with liquid electrolyte penetrating between layers. Tablet battery usually consists of multiple batteries, the new iPad battery consists of three batteries, but smart phones are usually powered by a battery. At the end of the battery, a printed circuit board connects the positive and negative electrodes of each cell and provides short-circuit protection, over-charge protection, and forced discharge protection. Lithium-ion batteries are fragile and require smartphone case protection so users cannot replace them.

2. Battery life Lithium-ion battery energy density determines the user's battery operating time under rated size and rated weight. In 1991 lithium-ion battery technology was introduced to the market. After that, the number of processor transistors exceeded 1,000 times and the lithium ion energy density only increased by a factor of three. Dense electronic components make a lot of cool features possible but require more energy consumption. Unfortunately, battery manufacturers have made slow progress in increasing energy density. This is why non-replaceable lithium-ion batteries are favored by designers of smartphones and tablet computers. Without a battery-safe cover, Li-ion sealed batteries will be thinner and provide longer battery life.

3. Battery volume and energy density are inseparable The energy density is affected by the ratio of the thickness and width (X) and length (Y) of the Li-ion sealed battery. Energy density decreases as the sealed package becomes thinner. When the printed circuit board is mounted on one end of a short and narrow battery, there will be no more space for the active material to store energy. With a constant volume, the narrow, thicker battery has a higher energy density.

4, the need to maintain the battery cooling Lithium ion sealed battery can not be too hot. The standard lithium-ion chemical reaction process depends on the hydrofluoric acid produced by the reaction of the electrolyte with excess moisture. Hydrofluoric acid is the most corrosive material of all compounds. As with all chemical reactions, every 10 degrees Celsius increase in temperature doubles the reaction rate, resulting in a reduction in battery life and cycle life: not only does the charge run time decrease, but the charge and discharge cycles are further reduced until no charge occurs. Consequences of use. What's worse is that lithium-ion batteries generate heat themselves during charging and discharging: the more energy a smartphone consumes or the faster it is charged, the hotter the battery is.

5, create a smart phone Motorola Droid Razr smart phone uses a three-tier design: display, circuit board and battery. The iPhone 4 uses a two-layer design: display screens and electronic devices: The printed circuit board makes room for the battery. In either case, a large display will mean more battery space. Despite the relatively high energy density of narrow and thick batteries, the three-tier solution also makes it difficult to protect the battery from heat generated by parts and shorten battery life.

6, the chemical reaction process: packaging ace lithium ion chemical reaction process to improve or significantly improve the energy density, smart phone designers in the conflict between the function and life time to provide more choices. At present, significant breakthroughs have been made in the research of active materials, and some new solutions have been introduced to the market. One of the new solutions is the use of a new lithium-imide electrolyte that does not generate hydrofluoric acid, significantly improves battery heat resistance and battery life, and allows the thickness of the battery to be reduced by eliminating the current thickness of lithium-ion battery seals. thin.

Bottom line Before new advances were made in lithium-ion sealed batteries, it is expected that Apple or other smart phone makers will not change their designs. It takes at least 12-18 months before a new breakthrough is possible. The new active material and new electrolyte will increase the follow-up time for each charge of the same size battery by 20%. This type of battery will provide more choices for the Apple iPhone 6, faster processor configuration, higher power consumption of the display and more applications without sacrificing battery life, and making the iPhone 6 continue to maintain its exquisite thin and light Exterior.