Billions of battery-powered devices are soon to be interconnected through the Cloud-based Industrial Internet of Things (IIoT), including transportation infrastructure, energy, environmental monitoring, smart manufacturing, healthcare, smart buildings, and industrial automation.
Use of primary and rechargeable lithium batteries eliminate the need for the impractical expense of hard-wiring to the electrical grid, which can cost up to $100 per foot to install. Generally, the more remote the application, the greater the need for an industrial grade lithium battery.
Wireless devices that draw low average daily current are predominantly powered by primary bobbin-type lithium thionyl chloride (LiSOCl2) chemistry, which offers unique advantages over all other lithium chemistries, including higher energy density, higher capacity, the widest temperature range, and a lower annual self-discharge rate.
The operating life of a bobbin-type LiSOCl2 cell depends largely on its annual energy usage and its annual self-discharge rate. In many cases, more energy is lost through annual battery self-discharge than through actual battery usage. How a battery is manufactured affects its annual self-discharge rate.
Tadiran offers superior quality bobbin-type LiSOCl2 cells that feature a self-discharge rate of 0.7% per year, retaining nearly 70% of their original capacity after 40 years. Lesser quality bobbin-type LiSOCl2 cells can have a self-discharge rate of 3% per year, exhausting 30% of their capacity every 10 years.
If the IIoT-related application requires high pulses, the recommended solution is a battery, which combines a standard LiSOCl2 cell with a patented hybrid layer capacitor (HLC). The standard LiSOCl2 cell delivers low background current to power the device is in its ‘standby’ mode, while the HLC delivers high pulses required for data interrogation and transmission.
batteries are advantageous to supercapacitors that store high pulses in an electrostatic field rather than in a chemical state. Supercapacitors have drawbacks for industrial applications, including short duration power, linear discharge characteristics that do not allow for use of all the available energy, low capacity, low energy density, and very high self-discharge (up to 60% per year). Supercapacitors linked in series also require cell-balancing circuits.
Certain applications may be well suited for energy harvesting in combination with rechargeable Lithium-Ion (Li-ion) batteries being used for energy storage.
Inexpensive consumer grade Li-ion cells have a life expectancy of less than 5 years and 500 recharge cycles and operate within a moderate temperature range of 0°C - 40°C. By contrast, industrial grade Li-ion batteries can operate for up to 20 years and 5,000 full recharge cycles, and offer an expanded temperature range of -40°C to 85°C, along with the ability to deliver high pulses (5A for a AA-size cell). Industrial grade rechargeable batteries are constructed with a hermetic seal instead of a crimped seal that may leak.
Bobbin-type LiSOCl2 cells and industrial grade Li-ion rechargeable batteries offer intelligent solutions for battery-powered devices used throughout the IIoT.