Denver-based Infinite Power Solutions is claiming 15,000 deep discharge cycles for its postage stamp battery technology, as well as 45mA/cm2 current density.
"We tested 0.7mAh, 1in.2 square-inch rechargeable cells to 100% depth of discharge [DOD] at 25°C for greater than 15,000 cycles at 9C rate with approximately 90% of their starting capacity maintained, as verified at the capacity-defining 0.5C rate," said IPS. "Other rechargeable batteries, such as Li-ion, Li-polymer and NiMH cells are usually cycled to only 80% DOD and rarely achieve 1,000 cycles with 80% capacity retention."
The company's technology, which is well under 1mm thick, has been dubbed Thinergy.
Inside is a lithium cobalt oxide cathode, a lithium anode, and a lithium phosphorus oxy-nitride solid electrolyte.
The electrolyte that is said to be the key to the technology - blocks electrons to the point that 1nA a self-discharge is claimed, far better than Li-ion cells or supercapacitors.
As such, the firm is proposing Thinergy for matching energy scavengers - which deliver energy slowly and unpredictably - with the high pulsed current demand of radio transmitters.
To underline the output current capability, the firm recently released the 45mA/cm2 figure, delivered from a 25.4x25.4x0.17mm cell.
"In recent tests, we demonstrated a continuous discharge current of 170mA at 25°C from a single device. This translates to an active area continuous current density of 45mA/cm2," said IPS. "Considering a starting discharge capacity of 0.7mAh, this current equates to a nominal 240 capacity rate [240C rate]. In comparison, a typical Li-ion cell phone battery delivers less than 10mA/cm2. Cell phone batteries typically generate less than 2C-rate."
Currently, the firm is specifying its standard products to 10,000 cycles at 100% DOD with 80% initial capacity retention.
"As testing continues, IPS expects its devices to achieve more than 20,000 cycles with 100% DOD and 80% capacity retention, and more than 100,000 recharge cycles with shallow cycling to 50% DOD," said the firm.
Terminal voltage is 4V and operating temperature range is -40 - 85°C.