TDK's surface-mountable, rechargeable solid state batteries are now available from TTI.
The TDK CeraCharge range merges aspects of lithium-ion battery and multilayer ceramic capacitor technologies to produce an all-ceramic, solid-state rechargeable cell suitable for reflow soldering. The parts can be used as backup batteries for real-time clock circuits, to store energy for Internet of Things (IoT) devices such as beacons and energy-harvesting systems, and as sub-batteries that smooth out voltage and current variations in wearable devices.
The solid state batteries use lithium-based ceramic oxides to form both the electrolyte and the inner electrode of the battery, and copper to collect the resultant charge and route it to the external electrodes. The parts therefore combine the benefits of lithium ion batteries with the safety and manufacturing advantages of ceramic multilayer components.
The all ceramic-structure of the CeraCharge batteries means that they cannot leak, burn or explode, and will work over wide operating temperature ranges and even in a vacuum. The parts are compatible with reflow soldering processes, surface mountable, and embeddable. They are available in EIA case sizes.
The CeraCharge 1812 measures 4.5 x 3.2 x 1.1 mm and weighs 40 mg. It has a nominal operating voltage of 1.5 V, a nominal capacity of 100 µAh, and a nominal discharge current of 20 µA. The battery’s chemistry has been optimised to enable it to handle fast, pulsed discharges, to serve the needs of devices such as IoT beacons that require irregular short bursts of energy.
Potential applications for the CeraCharge batteries include in smart meters and PLCs, for backing up their onboard real-time clocks; in sensors, tags, electronic shelf labels and robotics for supporting short-range RF beacon functions; and in wearable devices such as smart watches, fitness bracelets, and hearing aids.