Panasonic – World’s smallest cylindrical li-ion rechargeable battery ideal for wearable devices


The new CG-320A pin-type battery from Panasonic is the smallest cylindrical lithium-ion rechargeable battery on the market, just one-twentieth the size of an AAA battery.

Only 20mm long with a diameter of 3.65mm, and offering a nominal capacity of 15mAh, the CG-320A battery is intended for use in wearable devices such as smart watches, fitness trackers, virtual-reality glasses and digital pens. It can also be used in medical products such as hearing aids. Even though the CG-320A has a small diameter, it has the spiral electrodes normally used in lithium-ion rechargeable batteries.

The peak power output of the CG-320A is sufficient to support the operation of an NFC reader. Housed in a stainless steel can, the battery offers excellent stability and reliability.



  • Fast charging capability
  • 3.8V nominal voltage
  • 4.35V maximum charging voltage
  • 11.2mA maximum charging current
  • Operating-temperature range for discharging: -10°C to 60°C


  • Smart watches
  • Fitness trackers
  • Wearable devices
  • Hearing aids