Radio Frequency Testing

T.1 Altitude simulation test

·Store the cells and batteries in an environment with a temperature of 20±5°C and an atmospheric pressure of no more than 11.6kpa for no less than 6 hours

The open circuit voltage after the sample test should not be lower than 90% of the open circuit voltage before the test. This requirement does not apply to fully discharged batteries and cells.

The sample (battery) should have no leakage, no exhaust, no disassembly, no rupture and no fire.

T.2 thermal shock

·Battery storage conditions are as follows:

·A temperature cycle is 72±2°C (6h) — -40±2°C (6h)

The maximum interval between temperature conversion is 30min

· Repeat 10 times

After the cycle is over, the battery should be kept at 20±5°C for 24 hours.

The open circuit voltage after the sample test should not be lower than 90% of the open circuit voltage before the test. This requirement does not apply to fully discharged batteries and cells.

The sample (battery) should have no leakage, no exhaust, no disassembly, no rupture and no fire.

T.3 Vibration test

· Cells and batteries are firmly installed on the vibrating table (table top)

·The vibration is in the form of a sine wave, increasing from 7Hz to 200Hz, and then decreasing back to 7Hz as a cycle, and a cycle lasts 15 minutes for logarithmic forward transmission.

The logarithmic sweep is: start at 7 Hz with a maximum acceleration of 1 gn until a frequency of 18 Hz, then hold the amplitude at 0.8 mm (1.6 mm total excursion) and increase the frequency until a maximum acceleration of 8 gn (frequency around 50 Hz ), hold the maximum acceleration at 8gn until the frequency increases to 200 Hz.

·One of the directions of vibration must be perpendicular to the polarity of the sample, cycle 12 times for each cell from three mutually perpendicular directions, 3 hours in each direction, 9 hours in total.

The open circuit voltage after the sample test should not be lower than 90% of the open circuit voltage before the test. This requirement does not apply to fully discharged batteries and cells.

The sample (battery) should have no leakage, no exhaust, no disassembly, no rupture and no fire.

T.4 Impact test

·Fix all accessory surfaces of each cell and battery sample with a firm bracket.

·Impact each cell or battery with a half-sine acceleration peak value of 150gn and a pulse duration of 6 milliseconds. Large batteries and large battery packs must withstand a half-sine wave impact with a maximum acceleration of 50gn and a pulse duration of 11 milliseconds.

·Each battery or battery pack shall be subjected to three shocks in the positive direction of the three mutually perpendicular battery installation orientations, and then three shocks in the opposite direction, for a total of 18 shocks.

The open circuit voltage after the sample test should not be lower than 90% of the open circuit voltage before the test. This requirement does not apply to fully discharged batteries and cells.

The sample (battery) should have no leakage, no exhaust, no disassembly, no rupture and no fire.

T.5 External short circuit test

Keep the temperature of the test environment stable at 57±4°C, so that the surface temperature of the cell or battery sample can reach 57±4°C

·Short-circuit the positive and negative electrodes of the sample with a total resistance circuit less than 0.1Ω, and keep the short-circuit state for more than 1 hour after the surface temperature of the sample returns to 57±4°C.

·The cell or battery must be further observed for 6 hours before drawing conclusions.

During the test and within 6 hours thereafter, the cell or battery sample

- External temperature does not exceed 170°C

- No disassembly, no rupture and no fire.

T.6 Impact test

Shock (for cylindrical cells with a diameter of not less than 18 mm)

Put the cell or polymer cell used for the test sample on a flat and smooth surface

·After placing a crossbar with a diameter of 15.8mm across the middle of the battery, drop an object with a mass of 9.1kg to the sample from a height of 61±2.5cm.

• For specimens subjected to impact, the longitudinal axis shall be parallel to the flat surface and perpendicular to the longitudinal axis of a 15.8 ± 0.1 mm diameter curved surface placed across the center of the specimen. Each sample was subjected to only one impact.

The maximum surface temperature of the cell or battery should not exceed 170°C

Within 6 hours after the end of the test, there should be no disintegration and no fire phenomenon of the battery cell and polymer battery cell.

T.6 Extrusion test

Squeeze (suitable for prismatic, pouch, coin/button cells and cylindrical cells less than 18 mm in diameter)

• Press the cell or component cell between two flat surfaces with increasing force, at a speed of approximately 1.5 cm/s at the first point of contact. Extrusion continues until one of the following three conditions occurs:

- The applied force reaches 13 KN±0.78 KN

- The voltage of the battery has dropped by at least 100 mV

- The battery is deformed by more than 50% of its original thickness.

· Prismatic or pouch batteries should be pressed from the widest side. Button/coin cells should be pressed from their flat surface. Cylinders should be pressed from a direction perpendicular to the longitudinal axis.

The maximum surface temperature of the cell or battery should not exceed 170°C

Within 6 hours after the end of the test, there should be no disintegration and no fire phenomenon of the battery cell and polymer battery cell.

T.7 Overcharge test

·Charge the sample with 2 times the maximum continuous charging current recommended by the manufacturer

The minimum voltage for this test is:

·If the charging voltage recommended by the manufacturer does not exceed 18V, the minimum charging voltage for this test should be twice the maximum charging voltage calibrated by the manufacturer or 22V, whichever is smaller.

·If the charging voltage recommended by the manufacturer exceeds 18V, the minimum charging voltage for this test should be 1.2 times the maximum charging voltage calibrated by the manufacturer.

·At an ambient temperature of 20±5°C, the test lasts for 24 hours.

During the test and within 7 days after the test, the test sample should have no disassembly and no fire phenomenon.

T.8 Forced discharge test

·At an ambient temperature of 20±5°C, connect a single battery cell to a 12V DC power supply for forced discharge. The initial current provided to each battery cell by this DC power supply is the maximum discharge current specified by the manufacturer.

The specified discharge current is obtained by connecting a load of appropriate size and power in series on the test cell, and the mandatory discharge time (hour) of each cell is the rated capacity divided by the initial current (ampere).

During the test and within 7 days after the test, the test sample should have no disassembly and no fire phenomenon.

1.2m drop (after packaging)

The packaged lithium battery is dropped from 1200mm (the lowest point of the battery) to an 18-20mm thick hardwood board (the board is laid on the concrete floor) at 20±5°C.

The test sample does not catch fire or explode during and after the test.

Judgment Test Eligibility Criteria

(1) In tests T.1 to T.6, no disassembly or fire occurred.

(2) In tests T.1, T.2 and T.5, the effluent is not a toxic, flammable or corrosive substance.

a. Visual inspection does not see exhaust or leakage;

b. No venting or leakage occurs that would result in a weight loss in excess of that shown in Table 38.3.4.7.1.

(3) In tests T.3 and T.6, the effluent is not a toxic or corrosive substance.

a. Visual inspection does not see exhaust or leakage;

b. No venting or leakage occurs that would result in a weight loss in excess of that shown in Table 38.3.4.7.1.

(4) 1.2m drop from X, Y, Z positive and negative six directions, drop once in each direction, no leakage, no disassembly, no combustion, no explosion, no damage.