Technology & Quality


Quality Policy
Focused on Customer Satisfaction and managed with P-D-C-A cycle
EXA is committed to creativeness and continual improvement.

We assure the quality of EXA’s products and service processes with precision, promptness and
effectiveness and response quickly to market changes and customer requirements.

What We Insist - EXA

To provide an economical power solution to enhance the competitiveness for our customers.

To pursue the excellence in company management and product development.

To produce reliable product by devoting great efforts into RD and QA




Product safety is our most important responsibilty and we pay much attention in quality control.
Therefor, EXA follows the standard with UL 1642 continuously to control product safety strictly.

Safety Testing List of UL1642

Abnormal Charge

Short Circuit







Plaming Particles

Low Pressure

Temperature Cycling


Abnormal Charge
Testing condition
UL Test begins with constant at 3C.
When cell voltage rises to target max, test switches to constant Voltage.
If thermal runaway does not occur, the current will taper down.
Total charging time, 48h.
No Fire or Explosion

Short Circuit Test
Testing condition
Each test sample battery, in turn, is to be short-circuited by connecting the positive and negative
terminals of the battery with copper wire having a maximum resistance load of 0.1 ohm.The
battery is to discharge until a fire or explosion is obtained, or until it is completely discharged and
the battery case temperature has returned to near ambient temperature.

Tests are to be conducted at room temperature and at 60°C.The batteries are to reach equilibrium
at room temperature or 60°C, as applicable, before the terminals are connected.

When an overcurrent or thermal protective device that has been investigated for the purpose
actuates during the test, the test shall be repeated with the battery supply connected to the
maximum load that does not cause the protective device to open.
A protective device that has not
been investigated for the purpose shall be short-circuited.

The samples shall not explode or catch fire.
The temperature of the exterior cell or battery casing shall not exceed 150°C.

Heating Test
Testing condition
Temperature is raised at rate of 5°C per minute.
Temperature is held at 150°C for 10 minutes.
Cell is inspected.
No Fire or Explosion

Impact Test
Testing condition
9.1kg weight is dropped from a height of 610mm.
Force is transmitted to cell via 15.8mm diameter bar placed on top of cell.
Prismatic (retangular) cells are impacted on face and on side.
No Fire or Explosion

Crush Test
Testing condition
3000 lb (13kN) is aplied across a 1.25 in.(32mm) diameter piston, prismatic cells test on face
and on edge.

No Fire or Explosion

Temperature Cycling Test
Testing condition
Temp. raised to 70°C within 30 min and soaked for 4h.
Temp. reduced to 20°C within 30 min and soaked 2h.
Temp. reduced to -40°C within 30 min and soaked 4h.
Temp. raised to 20°C within 30 min.
Sequence repeated for 10 cycles total.
5g (and heavier) cells cannot leak more than 0.1% by weight.

Low Pressure
Testing condition
Batteries stored 6 h. at an absolute pressure of 11.6kPa (1.6 psi) and temperature of 20°C.
5g (and heavier) cells cannot leak more than 0.1% by weight.

Flaming Particle Test
Testing condition
c mounted 1-1/2 in. above top of burner.
Panel of cheesecloth layers position vertically from burner.
Battery is to be positioned horizontally in the center of the screen.
Vents directed towards cheesecloth.
Battery may be positioned 45 degrees to cheesecloth depending on vent construction.
The cheesecloth catch no fire.

Vibration Test
Testing condition
The frequency is to be varied at the rate of 1 Hz per minute between 10 and 55 Hz, and return in
not less than 90 nor more than 100 minutes.

The battery is to be tested in three mutually perpendicular directions.
For a battery that has only two axes of symmetry, the battery is to be tested perpendicular to each

The samples shall not explode or catch fire.

Shock Test
Testing condition
Each cell shall be subjected to a total of three shocks of equal magnitude.
The shocks are to be applied in each of three mutually perpendicular directions unless it has only
two axes of symmetry in which case only two directions shall betested.

Each shock is to be applied in a direction normal to the face of the cell.
The cell is to be accelerated in such a manner that during the initial 3 milliseconds the minimum
average acceleration is 75g.

The samples shall not explode or catch fire.

Projectile Test
Testing condition
Each cell is to be placed on a platform table haveing a 4 in. diameter hole in the center covered by
a screen.

The screen is to be of steel wire mesh having 20 openings per in. and a wire diameter of 0.017 in.
An eight-sided covered wire cage, 2 ft. across and 1 ft. high, made from metal screening is to be
placed over the test sample.

No part of an exploding cell or battery shall penetrate the wire screen such that some or all of the
cell or battery protrudes through the screen.