As battery technology goes, some have wider applications than others. The lithium-ion battery, first developed in the early 1990s, revolutionized the use of batteries. Allowing for massively increased battery efficiency, power output, and an increased number of charge cycles in the case of rechargeable batteries, this was one development that saw batteries start being used for much more than just small electric and electronic items. In many ways, this paved the way for the development of electric cars around a decade later, though it is only now that we are seeing them truly take over.
Batteries are now in vogue, as it were, and their expanded use has driven development in the technology. Products such as a USB rechargeable batteries, like those produced by Pale Blue Earth in Utah, are becoming ever more popular consumer items. Moreover, many more products that were previously powered by some other means are beginning to use batteries. Yet batteries of a greater size and efficiency is not the only technological development that has occurred in this time. One of the most impressive developments has been the appearance of wirelessly rechargeable batteries. These are batteries that require no direct electrical contact to transfer power from battery to device, instead doing so using a magnetic field. These batteries have yet to make the same impact that other new battery technologies have and remain limited to smaller electronic devices. This could be something, however, that could change very soon.
Mechanism
As mentioned, wireless charging involves the transfer of battery power across a magnetic field instead of a physical connection between a battery’s cathode and the circuit that receives the power. A wirelessly recharging battery system makes use of a magnetic coil to transfer energy across a field. The system is essentially a flat transformer, which makes it easier to fit inside small portable electronic devices. The power source is often contained within a mat or a pad and energy can be transferred when the receiver is brought within sufficient proximity. Wireless charging has found applications in products like smartphones and electric toothbrushes, where cordless charging is an advantage.
Advantages and Disadvantages
Wireless recharging removes the need for a physical connector. The main advantage here is that there is no chance of a battery connection becoming less efficient on account of wear after extended periods of use. These systems are also resistant to contamination from dirt and other external bodies that a physically connected battery is exposed to.
A definite disadvantage though is that there is a risk of the wireless power transfer (which occurs due to proximity alone) interfering with other electronics in range of the battery. It is for this reason that wirelessly recharging batteries requires physical screens, especially because they are typically used within small electronic devices where every part of the device is within proximity to the battery. This complex system and the need for screening also requires that the system be more expensive than alternatives, which could account for the relatively slow uptake of the technology compared to other devices.
The Future
The future of wireless charging seems to lie in the direction of the increased versatility of a wireless charger as well as expanding the range of devices that can be charged by a single wireless charging pad. We are not there yet, but should the technology be developed to the point where multiple items can be charged at the same time simply by being sat close to the charger, then this could massively expand the wireless charger’s appeal. At that point, we may begin to see wireless chargers everywhere.
