Flexible Lithium Polymer Batteryjflex

J.Flex is Jenax’s innovative flexible, solid-state, fast charging, rechargeable lithium-ion battery. Without sacrificing power, J.Flex can fully bend and move with your device to enable your new breakthrough technology.

Be free from product design limitations faced by tradition batteries with our flexible battery. Find your best energy storage solution with J.Flex – customized battery for wearables, IoT, and other connected devices.


The uses for J.Flex are limitless. From current wearable applications that span diverse industries to unforeseen future technologies, J.Flex can fully realize next generation creative design.

IT Wearables

  • Smart Watch
  • Smart Glasses
  • Headset

  • Fitness Band
  • Medical Device

  • Smart Apparel
  • Accessories
  • Footwear

  • GPS Tracker
  • Military Helmet
  • Wearable Robot


  • Gel polymer electrolyte
  • Rapid movement of lithium ion
  • No overheating
  • High energy density
  • Low internal resistance
  • Stable even with bending fatigue



J.Flex can be bent or rolled to enhance the flexibility of next generation devices. From IT to healthcare and fashion, J.Flex supports a range of industries that are using advanced technologies to add new design, comfort, and efficiency to their devices.

The test below tracks the charge and discharge performance of batteries in two different states:

1. Non-bending

2. Dynamic bending (10,000 bends from flat to 20mm in radius)


Even with constant dynamic bending, J.Flex performed at the same efficiency and capacity as the non-bending baseline level.


Creative designs are often hindered due to lack of components that support a designer’s vision. With J.Flex, a new level of customization is possible. A designer can now use new shapes and sizes not previously available without sacrificing performance.
J.Flex gives product designers freedom to create entirely new types of devices. Make your products more functional, discreet, and streamlined with J.Flex.


J.Flex ensures outstanding performance for any device.

The tests below are based on a J.Flex cell with the following specifications:

Category Contents
Type Li-ion Polymer
Dimension 27x48mm
Nominal Voltage 3.8V
Capacity 30mAh<@0.1C
Operation Temp. -20 ~ 60℃
Cycle 80%@1.0C/1,000cycle
Standard Current Charge 1.0C CC/CV to 4.25V, 0.1C cutoff
Discharge 0.2C to 3.0V
Max Current Charge 1.0C(30mA)
Discharge 2.0C(60mA)
  • High Rate Cycle (1.0c Charge & Discharge)graph2
  • Charging Rategraph3
  • Discharge Rategraph4


J.Flex is in compliance with international standards to ensure safety for all applications.

Electrical Abuse Test

  • Short Circuit Test
    At 55±5˚C, with a 100mΩ until 20% decrease from the highest temp.Pass
  • Over Charge Test
    DC 10V (20±5˚C)
    1. charge current: 1C
    2. charge time > 2.5 hrsPass
  • Over Discharge Test
    1C discharge for 90 minPass
  • Over Current Test
    4.2V CC/CV charge with max.
    3C (20±5˚C)Pass

Environmental Abuse Test

  • High Temperature Test
    Storage 70±2˚C for 7 hrsPass
  • Low Pressure Test
    Storage at 11.6KPa for 6 hrsPass
  • Heating Test
    Increase 5±2˚C/min till 130±2˚C and keep 130±2˚C for 10 minPass

Mechanical Abuse Test

  • Impact Test
    Drop 9.1±0.1Kg weight at a height of 61±2.5cm from the cellsPass
  • Drop Test
    Drop cells on to hardwood from 1m height 3 times (20±5˚C)Pass
  • Nail Penetration Test
    Penetration of fully charged battery pack
    1. nail radius = 3mm
    2. penetration rate = 80mm/secPass