Smartphone battery science – how phone batteries work and what is next for them, defines the amazing technology behind the item which gives an enormous contribution to the existence of modern phones and computer tablets that flood the market today. No matter how well-designed, how modern and how powerful, mobile devices could not just do their jobs without batteries.
How long a smartphone battery can make the device alive and how fast they can recharge to get back to work are among the major areas researchers are exploring these days. As a new year rushes in, many original equipment manufacturers are bracing themselves to introduce new mobile devices and this year is expected to see more exciting innovations. Android Central gives a detailed post about the very important component of mobile devices, the smartphone battery science – how phone batteries work and what is expected of them next.
Majority of portable electronics today are using rechargeable batteries, which in themselves, use lithium-based chemistry with lithium-ion and lithium-polymer as the most common. Li-ion batteries offer high energy density and are lightweight. They come in button cells or long metal cylinders similar to AA batteries. They can be charged 500 to a thousand times. This battery is used in many mobile devices like the Motorola Droid Maxx and HTC One M8 Verizon.
Li-po batteries, which were introduced later, use solid polymer composite to replace the liquid solvent. They are similar to li-ion batteries but are slimmer. They can be charged 300 to 500 times. The li-po battery is more flexible as it is encased in plastic lamination in lieu of the metallic casing. This type of battery is featured in some laptops and smartphones, such as the Nokia Lumia 928 Verizon.
A lithium-based smartphone battery works in a way wherein lithium ions move from a positive electrode called “anode”, to the negative electrode, “cathode” via an electrolyte solution, thus, releasing electricity to the circuit and gives power to the smartphone or tablet. This process reverses when the battery is charging, and the anode absorbs the ions. The battery’s capacity is determined on the number of ions the anode can absorb. Most modern batteries have anodes made out of graphite, which absorption capacity is maximized as much as possible.
Lithium batteries degrade fast during higher temperatures caused by charging and device usage. That is why low amperage chargers are recommended for overnight charging.
Smartphone battery aging process is defined by the structural and chemical changes to the electrodes. The movement of ions itself can damage the highly-ordered surface of the electrodes, and over time, the lithium salts in the electrolyte can harden on the electrodes, clog up the pores and prevent the uptake of ions. The ratio of the number of electrons retrieved from the anode to the number of electrons absorbed during charging is called coulombic efficiency. For a battery to be commercially viable, the coulombic efficiency should be 99.9 percent.
However, lithium-based batteries can overheat, overload, short and puncture. When heat builds up, it can trigger a thermal runaway and explode. Charging circuits of portable devices are designed to prevent these adverse things from happening, but it can really be dangerous if they fail. Ventilation is also required to cool the heating battery and stop the building up of flammable solvents if they leak, hence, reduce explosion risks.
In the near future, the smartphone battery will definitely be of higher capacity, longer lifespan, safer and faster charging. The current li-po tech is enhancing the anode material to improve battery capacity and longevity, as well as absorption rates that make charging faster. For a longer smartphone battery lifespan, a more resilient material for anode should be used. In research is the electrolyte between electrodes, plus the cost reduction of producing battery individual components.
Scientists are looking for ways to make safer lithium batteries. The University of North Carolina announced last year their discovery of perfluoroplyether or PFPE oil to replace the flammable solvents in lithium batteries. PFPE oils are used as industrial lubricants and have been found to easily dissolve lithium salts, better than the currently-used solvents. Such would lessen the hardening effect on the electrodes, and prolong battery life. This calls for further testing though, but the tech industry will be getting non-flammable lithium smartphone battery soon.
In case of faster charging, a Nangyang Technological University research group developed a li-on battery that can be filled 70 percent within two minutes, and can endure 10,000 cycles – a very attractive concept to the industries of electronic vehicle and mobile. Titania-made titanium dioxide nanotubes replace graphite anode. A naturally-occurring titanium compound, titania is cheap and it is used in sunscreen and skimmed milk as it can improve whiteness. Using gel of nanotubes can increase the battery surface part so the anode can make ions uptake quicker.
The study group likewise found that titanium dioxide absorbs more ions and less prone to aging than graphite. Furthermore, titanium nanotubes are simple to make – after being mixed with lye, titania is heated, dilute acid-washed and heated again for 15 hours. This discovery is already patented and it will perhaps make it to the market before long.
Meanwhile, firms like Qualcomm use chips that allow them to maximize input charge without overheating the smartphone battery or harming its internal circuits. The QuickCharge feature, for instance, is found in HTC One M8, Galaxy Note 4 and Nexus 6.
While studies are ongoing with regard to smartphone battery science, how smartphone batteries work, how to enhance their performance and what there is to offer next, the current tech market already has devices with impressive batteries. According to the Laptop tech site, today’s smartphones that have the longest battery lives include Huawei Ascend Mate 2 (14 hours and 43 minutes), OnePlus One (13 hours and 16 minutes), Sony Xperia Z3 (12 hours and 9 minutes), Nokia Lumia 1520 AT&T (11 hours and 28 minutes), Samsung Galaxy S5 (10 hours and 57 minutes) and iPhone 6 Plus (10 hours).
By Judith Aparri
Photo courtesy of Josh Bancroft – Flickr License
Feature Photo by SamsungTomorrow – Flickr License