Thông tư 07/2016/TT-BTTTT

CIRCULAR

PROMULGATING “NATIONAL TECHNICAL REGULATION ON LITHIUM BATTERIES FOR PORTABLE APPLICATIONS”

Pursuant to the Law on Technical regulations and standards dated June 29, 2006; The Law on telecommunications dated November 23, 2009;

Pursuant to the Government's Decree No. 127/2007/ND-CP dated August 01 2007 detailing the implementation of a number of articles of the Law on Technical regulations and standards;

Pursuant to the Government's Decree No. 132/2013/ND-CP dated October 16, 2013 defining the functions, tasks, entitlements and organizational structure of the Ministry of Information and Communications;

At the request of Director of the Department of Science and Technology,

The Minister of Information and Communications promulgates a Circular promulgating National Technical Regulation on lithium batteries for portable applications.

Article 1. National Technical Regulation on lithium batteries for portable applications (QCVN 101:2016/BTTTT) is promulgated together with this Circular.

Article 2. This Circular comes into force from October 01, 2016.

Article 3. Chief of Office, Director of the Ministry of Science and Technology, heads of agencies and units affiliated to the Ministry of Information and Communications, Directors of Provincial Services of Information and Communications, relevant organizations and individuals are responsible for the implementation of this Circular./.

QCVN 101:2016/BTTTT

NATIONAL TECHNICAL REGULATION ON LITHIUM BATTERIES FOR PORTABLE APPLICATIONS

TABLE OF CONTENT

1. GENERAL PROVISIONS

1.1. Scope

1.2. Regulated entities

1.3. References

1.4. Definitions

1.5. Markings

1.6. Abbreviations

2. TECHNICAL PROVISIONS

2.1. Electrode requirements

2.2. Physical appearance

2.3. Labels and markings

2.3.1. Markings

2.3.2. Marking

2.4. Cell requirements

2.5. Electrical requirements

2.5.1. Nominal voltage

2.5.2. Rated capacity

2.5.3. Discharge capacity

2.5.4. Charge capacity

2.5.5. Internal resistance

2.5.6. Endurance in cycles

2.5.7. Electrostatic discharge (ESD)

2.6. Safety requirements

2.6.1. Intended use

2.6.2. Reasonably foreseeable misuse

2.7. Parameter measurements tolerances

2.8. Electrical tests

2.8.1. Electrical tests

2.8.2. Test protocol and conditions for sampling

2.9. Safety tests

2.9.1. Testing conditions

2.9.2. Charging procedure for testing purposes

2.9.3. Intended use

2.9.4. Reasonably foreseeable misuse

3. INSTITUTIONAL PROVISIONS

4. RESPONSIBILITIES

5. IMPLEMENTATION

BIBLIOGRAPHY

Foreword

QCVN 101:2016/BTTTT is based on IEC 61960 (06-2011): “Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary lithium cells and batteries for portable applications” and IEC 62133 (2012): “Secondary cells and batteries containing alkaline or other non-acid electrolytes - Safety requirements for portable sealed secondary cells, and for batteries made from them, for use in portable applications”.

QCVN 101:2016/BTTTT is compiled by Postal Technology Institute, appraised and submitted by the Ministry of Science and Technology, promulgated by the Ministry of Information and Communications together with Circular No. 07/2016/TT-BTTTT dated March 17, 2016.

NATIONAL TECHNICAL REGULATION ON LITHIUM BATTERIES FOR PORTABLE APPLICATIONS

1. GENERAL PROVISIONS

1.1. Scope

This Regulation provides for minimum requirements for lithium batteries for portable applications, including cell phones, tablets, laptops.

1.2. Regulated entities

This Regulation applies to organizations and individuals manufacturing, trading in devices regulated by this Regulation within Vietnam’s territory.

1.3. References

IEC 61000-4-2 (2008): “Electromagnetic compatibility (EMC) - Part 4-2: Testing and measurement techniques - Electrostatic discharge immunity test”.

IEC 62281 (2012): “Safety of primary and secondary lithium cells and batteries during transport”.

1.4. Definitions

1.4.1. Nominal voltage

The voltage written on the label of a cell or battery.

Note:

- The nominal voltages of secondary lithium cells are specified in Table 1.

- The nominal voltage of a battery of n series connected cell is equal to n times the nominal voltage of a single cell.

1.4.2. Final voltage/end-of-discharge voltage

The voltage at which a discharge of a cell or battery is terminated.

1.4.3. Rated capacity

Quantity of electricity C5 (Ah) declared by the manufacturer which a single cell or battery can deliver for 5 consecutive hours when charged, discharged, and stored under the conditions specified in 2.8.1.2.1.

1.4.4. Discharge capacity

Capacity of the cell/battery during discharge.

1.4.5. Charge capacity

Capacity of the cell/battery during charge.

1.4.6. Internal resistance

Resistance of the cell/battery declared by the manufacturer.

1.4.7. Life cycles

The number of charge/discharge cycles which a cell/battery can endure before its useful capacity has been significantly depleted. Such capacity shall not fall below the values specified in Table 2.

1.4.8. Secondary cell

A device which provides a source of electrical energy by direct conversion of chemical energy, consists of electrodes, separators, electrolyte, container, and is designed to be charged electrically.

1.4.9. Secondary lithium battery

A unit which incorporates one or more secondary lithium cells and is ready for use. It has housing, terminal arrangement and electronic control devices.

1.4.10. Secondary lithium cell

A single secondary cell whose electrical energy is derived from oxidation and reduction of lithium. It is not ready for use in an application because it does not have housing, terminal arrangement and electronic control device.

1.4.11. Intended use

The use of a product, process or service in accordance with specifications, instructions and information provided by the manufacturer.

1.4.12. Reasonably foreseeable misuse

The use of a product, process or service in a way which is not intended by the manufacturer, but which may result from readily predictable human behavior.

1.4.13. Leakage

Visible escape of liquid electrolyte.

1.4.14. Explosion

Failure that occurs when a cell container or battery case opens violently and major components are forcibly expelled.

1.4.15. Fire

The emission of flames from a cell or battery.

1.4.16. Upper limit charge voltage

Maximum charge voltage in the cell activity field specified by the cell manufacturer.

1.4.17. Maximum charging current

Maximum charging current in the cell activity field specified by the cell manufacturer.

Symbols

A                    Ampere

Ah                  Ampere-hour

kV                  Kilovolt

V                    Volt

mV                 miliVolt

Ω                    Ohm

mΩ                 miliOhm

ºC                   Celsius degree

m                   meter

mm                 millimeter

N                    Newton

kN                  kiloNewton, 1 kN = 1 x 10³ N

kHz                 kilohertz

Abbreviations

AC                  Alternating current

DC                 Direct current

2. TECHNICAL PROVISIONS

2.1. Electrode requirements

The positive and negative electrodes of the cell/battery must be bright and clean, has no rust and ensure good electrical contact.

2.2. Physical appearance

The cell/battery must be clean, has no stain or traces of salt and must not be deformed in a manner that obstructs its operation; its label must be clear.

2.3. Designation and marking

2.3.1. Designation

Batteries shall be designated in the following format:

N₁ A₁ A₂ A₃ N₂ / N₃ / N₄ - N₅

Cells shall be designated in the following format:

N₁ A₁ A₂ A₃ N₂ / N₃ / N₄

Where:

- N₁ is the number of series connected cells in the battery;

- A₁ designates the negative electrode in which:

l is lithium ion (Li-ion);

L is Lithium metal or lithium alloy.

- A₂ designates the positive electrode in which:

C is cobalt;

N is nickel;

M is manganese;

V is vanadium;

Ti is titanium;

- A₃ designates the shape of the cell in which:

R is cylindrical;

P is prismatic.

- N₂ is the maximum diameter (if R) or maximum thickness (if P) in mm rounded up to the next whole number;

- N₃ is the maximum width (if P) in mm rounded up to the next whole number (N₃ not shown if R);

- N₄ is the maximum height in mm rounded up to the next whole number;

NOTE: if any dimension is less than 1 mm, the unit used is tenths of millimeters (1/10 mm) and the single number is written responsibilities.

- N₅ is the number of parallel connected cells if 2 or greater (not shown if value is 1).

Example 1: ICR19/66 designates a cylindrical Li-ion secondary cell, with a cobalt-based positive electrode, a maximum diameter between 18 mm and 19 mm, and a maximum height between 65 mm and 66 mm.

Example 2: ICP9/35/150 designates a prismatic Li-ion secondary lithium cell, with a cobalt-based positive electrode, a maximum thickness between 8 mm and 9 mm, a maximum width between 34 mm and 35 mm, and a maximum overall height between 149 mm and 150 mm.

Example 3: ICPt9/35/48 designates a prismatic Li-ion secondary lithium cell, with a cobalt-based positive electrode, a maximum thickness between 0.8 mm and 0.9 mm, a maximum width between 34 mm and 35 mm, and a maximum overall height between 47 mm and 48 mm.

Example 4: 1ICR20/70 designates a cylindrical Li-ion secondary battery with one single cell, a cobalt-based positive electrode, a maximum diameter between 19 mm and 20 mm, and a maximum height between 69 mm and 70 mm.

Example 5: 2ICP20/34/70 designates a prismatic Li-ion secondary battery with two series connected cells, a cobalt-based positive electrode, a maximum thickness between 19 mm and 20 mm, a maximum width between 33 mm and 34 mm, and a maximum height between 69 mm and 70 mm.

Example 6: 1ICP20/68/70-2 designates a prismatic Li-ion secondary battery with two parallel connected cells, a cobalt-based positive electrode, a maximum thickness between 19 mm and 20 mm, a maximum width between 67 mm and 68 mm, and a maximum between 69 mm and 70 mm

2.3.2. Marking

Each cell or battery shall have clear and durable markings giving the following information:

- Secondary (rechargeable) Li or Li-ion;

- Battery or cell designation as specified in 2.3.1;

- Polarity;

- Date of manufacture;

- Name or identification number of the manufacturer.

Battery markings shall provide the following information:

- Rated capacity;

- Nominal voltage.

2.4. Cell requirements

Table 1 lists secondary lithium cells suitable for standardization and used in battery assembly.

Table 1. Secondary lithium cells

NOTE: The final voltage of a battery of n series connected cells is equal to n times the final voltage of a single cell as specified in Table 1.

2.5. Electrical requirements

2.5.1. Nominal voltage

The value of nominal voltage must not exceed the value declared by the manufacturer.

2.5.2. Rated capacity

The value of rated capacity must not exceed the value declared by the manufacturer.

2.5.3. Discharge capacity

Discharge capacity values are specified in Table 2.

2.5.4. Charge capacity

Charge capacity values are specified in Table 2.

2.5.5. Internal resistance

The value of internal resistance must not exceed the value declared by the manufacturer.

2.5.6. Endurance in cycles

Endurance in cycles is specified in Table 2.

2.5.7. Electrostatic discharge (ESD)

The battery must work normally under electrostatic discharge.

Table 2. Minimum requirements for various types of secondary lithium batteries/cells

2.6. Safety requirements

The safety of cells/batteries must be ensured under:

- Intended use;

- Reasonably foreseeable misuse.

2.6.1. Intended use

2.6.1.1. Continuous charge at constant voltage (cells)

The continuous charge at constant voltage shall not cause fire, explosion, or leakage.

2.6.1.2. Battery case in high ambient temperature

The battery case shall not be physically deformed and expose inner parts of the battery throughout the use in high ambient temperature.

2.6.2. Reasonably foreseeable misuse

2.6.2.1. External short-circuit

Short-circuiting of the positive and negative terminals in ambient temperature shall not cause fire or explosion.

2.6.2.2. Free fall

Dropping a cell/battery shall not cause fire or explosion.

2.6.2.3. Thermal abuse (cell)

An extremely high temperature shall not cause fire or explosion.

2.6.2.4. Crushing of cells

Severe crushing of a cell shall not cause fire or explosion.

2.6.2.5. Overcharge (battery)

Charging for longer periods than specified by the manufacturer shall not cause fire or explosion.

2.6.2.6. Forced discharge (cells)

Polarity reversal of a cell in a multi-cell battery shall not cause fire or explosion.

2.6.2.7. Movement

The manufacturer's manual must contain instructions on movement of lithium batteries under UN provisions for transport of dangerous goods.

2.6.2.8. Forced internal short-circuit (cells)

Forced short-circuiting of a cylindrical or prismatic cell shall not cause fire.

2.7. Parameter measurements tolerances

The accuracy of controlled or measured values shall be within the following tolerances:

a) ± 1% for voltage;

b) ± 1% for current;

c) ± 1% for capacity;

d) ± 2ºC for temperature;

e) ± 0.1% for time;

f) ± 0.1% for weight;

g) ± 0.1 mm for dimension.

These tolerances comprise those of measuring instruments, measurement techniques used and other tolerances in the test.

Measuring instruments used must be recorded in the result sheet.

2.8. Electrical testing methods

2.8.1. Electrical tests

All tests described in this clause shall be performed in still air. Charge and discharging currents for the tests shall be based on the value of the rated capacity C₅ (Ah). These currents are expressed as a multiple of I_t (A), which is the nominal current which can fully charge the battery in one hour.

The minimum values for each test are specified in Table 2. Sample sizes and sequence of tests are described in Figure 1.

2.8.1.1. Charging procedure for testing purposes

Prior to charging, the cell or battery shall be discharged at 20ºC ± 5ºC at a constant current of 0.2 I_t (A) down to a specified final voltage.

Sample shall be charged in a temperature of 20ºC ± 5ºC using the method declared by the manufacturer.

2.8.1.2. Discharge performance

2.8.1.2.1. Discharge performance at 20ºC

This test verities the rated capacity of a sample.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 2: The sample shall be stored in a temperature of 20°C ± 5 °C, for 1 – 4 hours.

Step 3: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 4: The capacity (Ah) delivered during step 3 shall not be smaller than the rated capacity declared by the manufacturer. Steps 1 to 4 may be repeated up to four times as necessary to satisfy this requirement.

2.8.1.2.2. Discharge performance at -20ºC

This test verities the rated capacity of a sample at a low temperature.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 2: The sample shall be stored in a temperature of -20ºC ± 2ºC, for 16 – 24 hours.

Step 3: The sample shall be discharged in a temperature of -20ºC ± 2ºC at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 4: The capacity (Ah) delivered during step 3 shall not be smaller than the rated capacity specified in Table 2.

2.8.1.2.3. High rate discharge performance at 20ºC

This test verities the rated capacity of a sample when discharged at a high rate. This test is not required if the sample is not designed to be used at this rate.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 2: The sample shall be stored in a temperature of 20ºC ± 5ºC, for 1 – 4 hours.

Step 3: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 1.0 I_t(A) until its voltage is equal to the specified final voltage.

Step 4: The capacity (Ah) delivered during step 3 shall not be smaller than that specified in Table 2.

2.8.1.3. Charge retention and recovery

This test determines the capacity which a sample retains after storage for an extended period of time and the capacity that can be recovered by a subsequent recharge.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 2: The sample shall be stored in a temperature of 20ºC ± 5ºC for 28 days.

Step 3: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 4: The capacity (Ah) delivered during step 3 in 28 days shall not be smaller than that specified in Table 2.

Step 5: The sample shall be charged in accordance with 2.8.1.1, and discharged as specified in step 3 within the next 24 hours.

Step 6: The sample shall be stored in a temperature of 20 °C ± 5 °C for 1 – 4 hours.

Step 7: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 8: The recovery capacity (Ah) delivered during step 6 shall not be smaller than that specified in Table 2.

2.8.1.4. Charge recovery after long-term storage

This test determines the capacity of a sample after extended storage at 50 % state of charge, followed by a subsequent charge.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 3: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) for 2.5 hours.

Step 3: The sample shall be stored in a temperature of 40ºC ± 2ºC for 90 days.

Step 4: The sample shall be charged in a temperature of 20 °C ± 5 °C, using the method declared by the manufacturer.

Step 5: The sample shall be stored in a temperature of 20°C ± 5°C for 1 – 4 hours.

Step 6: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 7: The capacity (Ah) delivered during step 5 shall not be smaller than the capacity specified in Table 2. Steps 4 and 5 may be repeated up to four times as necessary to satisfy this requirement.

2.8.1.5. Endurance in cycles

This test determines the number of charge/discharge cycles which a sample can endure before its useful capacity has been significantly depleted or the remaining capacity after a specified number of cycles.

Prior to charging, the cell or battery shall be discharged at 20°C ± 5°C at a constant current of 0.2 I_t(A) down to a specified final voltage.

The following endurance test shall then be carried out, irrespective of cell designation, in a temperature of 20 °C ± 5 °C. Charge and discharge shall be carried out in accordance with the conditions specified in either Tables 4 or 5. Sample sizes and sequence of tests are specified in Figure 1.

2.8.1.5.1. Endurance in cycles at a rate of 0.2 It (A)

Table 3. Endurance in cycles at a rate of 0.2 I_t (A)

The total number of cycles obtained when the test is completed shall be not smaller than that specified in Table 2.

2.8.1.5.2. Endurance in cycles at a rate of 0.5 I_t (A)

The procedures are the same as those in 2.8.1.5.1 at 0.5 I_t (A).

Table 4. Endurance in cycles at a rate of 0.5 I_t (A)

The remaining capacity obtained when the test is completed shall be not smaller than that specified in Table 2.

Step 1: The sample shall be charged in accordance with 2.8.1.1.

Step 2: The sample shall be discharged in a temperature of 20°C ± 5°C at a constant current of 0.2 I_t(A) until its voltage is equal to the specified final voltage.

Step 3: The sample shall be charged using a method declared by the manufacturer in a temperature of 20°C ± 5°C. The sample may be stored between step 2 and step 3, and after step 3 for each hour.

Step 4: The sample is continuously discharged and charged following steps 2 and 3 until a minimum capacity of 60% of the rated capacity is delivered.

Step 5: The number of times step 2 is repeated before completion according to step 4 shall not be smaller than that specified in Table 2.

2.8.1.6. Battery internal resistance

This test determines the internal resistance of a battery by either the alternating current (AC) or by the direct current (DC) method.

Should the need arise for the internal resistance to be measured by both AC and DC methods on the same battery, then the AC method shall be used first followed by the DC method. It is not necessary to discharge and charge the battery between conducting AC and DC measurements.

Step 1: The sample shall be charged in accordance with 2.8.1.1;

Step 2: The sample shall be stored in a temperature of 20ºC ± 5ºC for 1 – 4 hours.

Step 3: The measurement of internal resistance shall be suitable for 2.8.1.6.1 and 2.8.1.6.2 in an ambient temperature of 20°C ± 5°C.

2.8.1.6.1. Measurement of the internal AC resistance

The alternating r.m.s. voltage, U_a, shall be measured while applying an alternating r.m.s. current, I_a, at the frequency of 1.0 kHz ± 0.1 kHz to the battery for 1 - 5 seconds.

All voltage measurements shall be made at the terminals of the sample independently from the

The internal AC resistance R_ac shall be determined using the following formula:

R_ac = U_a / I_a (Ω)

Where:

- U_a is the alternating r.m.s. voltage;

- I_a is the alternating r.m.s. current.

NOTE 1: The alternating current is selected so that the peak voltage stays below 20 mV.

NOTE 2: This method will in fact measure the impedance at a specified frequency, which is approximately equal to the resistance declared by the manufacturer.

2.8.1.6.2. Measurement of the internal DC resistance

The battery shall be discharged at a current of I₁ = 0.2 I_t A. During last 10 seconds of a discharge, the discharge voltage U₁ under load shall be measured and recorded. The discharging current shall then be increased to a value of I₂ = 1.0 I_t A and the corresponding discharge voltage U₂ measured under load and recorded again during the last 1 second of a discharge.

All voltage measurements shall be made at the terminals of the battery independently from the

The internal resistance of the cell shall be calculated using the following formula:

R_dc = (U₁-U₂) / (I₂-I₁) (Ω)

Where:

- I₁, I₂ are constant discharging currents;

- U₁, U₂ are respective voltages measured during discharge.

2.8.1.7. Electrostatic discharge (ESD)

This test is to evaluate the ability of a battery to withstand electrostatic discharge.

This test shall be conducted on a battery containing electronic protection devices, such as diodes, transistors or integrated circuits.

This test shall be conducted in accordance with IEC 61000-4-2 which concerns electronic discharge requirements.

Batteries shall be tested at a constant discharge voltage of 4 kV and air discharge voltage of 8 kV.

2.8.2. Test protocol and sampling requirements

2.8.2.1. Test protocol

The sample size and protocol for conducting electrical tests are specified in Figure 1.

2.8.2.2. Sampling requirements

2.8.2.2.1. Dimensions

The dimensions of the sample shall not exceed the manufacturers' specified values and those values listed in Table 1.

2.8.2.2.2. Electrical tests

a) The rated capacity of the sample shall be declared by the manufacturer under the conditions specified in 2.8.1.2.1 and Table 5;

b) In order to meet the requirements of this Regulation, all samples shall meet all the requirements specified in Table 2. The minimum levels for meeting the requirements of the electrical tests are expressed as percentages of the rated capacity;

c) If the test results do not meet the conditions of 2.8.2.2.2.b, the test can be repeated with new samples, provided that, on any test, not more than one sample failed to reach the

d) To repeat the tests, the manufacturer may reduce the rated capacity of the battery to a value such that all test results do meet the conditions of 2.8.2.2.2.b.

2.8.2.2.3. Conditional sampling

It shall be considered that a sample meets all conditions of the charge recovery after long-term storage test specified in 2.8.1.4 and endurance test specified in 2.8.1.5 if:

a) 20 % of the required cycles of the endurance test have been completed and the capacity delivered throughout step 2 remains above 85 % of the rated capacity, and

b) the requirements of all tests specified in 2.8.1 have been met.

Figure 1. Sample sizes and sequence of tests

2.9. Safety tests

2.9.1. Testing conditions

The tests are made with the number of samples specified in Table 1 which are not more than 6 months old. Unless otherwise specified, the tests shall be carried out in an ambient temperature of 20°C ± 5°C.

Table 1 – Sample sizes

2.9.2. Charging procedures for testing purposes

2.9.2.1. First procedure

 (This charging procedure applies to the tests not specified in 2.9.2.2).

Unless otherwise stated, the charging procedure for testing purposes is carried out in an ambient temperature of 20°C ± 5°C, using the method specified by the manufacturer.

Prior to charging, the cell or battery shall be discharged at 20ºC ± 5ºC at a constant current of 0.2 I_t (A) down to a specified final voltage.

2.9.2.2. Second procedure

 (This procedure only applies to 2.9.4.1, 2.9.4.2, 2.9.4.4, 2.9.4.5 and 2.9.4.9).

Af_ter stable for 1 – 4 hours at the maximum and minimum temperatures specified in Table 6 (for LiCoO₂), the sample is charged at upper limit charge voltage and a maximum charging current until charging current drops to 0.05 I_t(A), using constant voltage method.

Table 6. Conditions for charge procedure

If the upper and/or lower limit charge temperature of the cell exceeds the limit specified in Figure 1, the cell shall be charged at an upper limit temperature of 50ºC and lower limit temperature of 5ºC in accordance with 2.9.4.1, 2.9.4.2, 2.9.4.4, 2.9.4.5 and 2.9.4.9 with a sound reason to ensure safety of the cell.

NOTE 1: If the upper limit charge voltage is not 4.25 V (different from LiCoO₂ system), the upper limit charge voltage and upper limit charge temperature may be adjusted to meet requirements in 2.9.4.1, 2.9.4.2, 2.9.4.4, 2.9.4.5 and 2.9.4.9 with a sound reason to ensure safety of the cell.

NOTE 2: For a new chemical system, a new charge procedure shall be specified in this document when information about such system comes into force.

2.9.3. Intended use

2.9.3.1. Continuous charge at constant voltage (cells)

The battery shall be charged to the level specified by the manufacturer in 07 days.

2.9.3.2. Battery container in high ambient temperature

Each battery is fully charged in accordance with 2.9.2.1 and placed in a circulating air-convection oven in a temperature of 70ºC ± 2ºC for about 7 hours. Then the battery is taken out and placed in ambient temperature.

2.9.4. Reasonably foreseeable misuse

2.9.4.1. External short circuit (cell)

The cells shall be fully charged in accordance with 2.9.2.2. Each cell shall be short-circuited by connecting the positive and negative terminals with a total external resistance of 80 mΩ ± 20 mΩ. The cell shall be measured for 24 hours or until the external surface temperature drops by 20% of the maximum temperature rise.

2.9.4.2. External short circuit (battery)

The batteries shall be fully charged in accordance with 2.9.2.2 in an ambient temperature of 55ºC ± 5ºC. Each battery shall be short-circuited by connecting the positive and negative terminals with a total external resistance of 80 mΩ ± 20 mΩ. The battery shall be measured for 24 hours or until the external surface temperature drops by 20% of the maximum temperature rise. However, if the short-circuited current drops quickly, the test duration may be increased by one more hour after the current reach a low stability. Such stability is reached when the voltage of each cell (only series connected cells) of the battery is below 0.8 V and drops by less than 0.1 V in 30 minutes.

2.9.4.3. Free fall

Each sample is fully charged in accordance with 2.9.2.1. and then dropped 3 times from a height of 1 m onto a concrete floor. The samples may be dropped so as to obtain impacts in random orientations. This test shall be carried out in an ambient temperature of 20ºC ± 5ºC. After that, the sample shall be left still for at least 1 hour and then inspected visually.

2.9.4.4. Thermal abuse (cell)

Each cell is fully charged in accordance with 2.9.2.2 and placed in a gravity or circulating air-convection oven. The oven temperature is raised at a rate of 5°C/min ± 2°C/min to a

2.9.4.5. Crushing of cells

Each cell is fully charged in accordance with 2.9.2.2 at the upper limit charge temperature, then crushed by a hydraulic ram exerting a force of 13 kN ± 1 kN. The test is carried on until a voltage drop of 1/3 of the nominal voltage or 10% deformation.

2.9.4.6. Overcharge (battery)

The test is performed in an ambient temperature of 20°C ± 5°C. The battery is discharged at a constant current of 0.2 I_t (A) to a final voltage specified by the manufacturer. _the sample is then charged at a constant current of 0.2 I_t (A) using a supply voltage (not exceeding the maximum voltage delivered by a recommended charger, otherwise this value will be 5V/cell) to sustain the constant current. The sample is attached to an electric thermometer throughout the test. For battery box, the temperature is measured on the box. The test is carried on until the box temperature is stable (changing by less than 10 ºC in 30 minutes) or is equal to ambient temperature.

2.9.4.7. Forced discharge (cells)

A cell is discharged and subject to a reverse charge at 1 x I_t (A) for 90 minutes

2.9.4.8. Movement

Test requirements are defined in UN guidelines for movement of dangerous goods. Movement tests are provided for in IEC 62281.

2.9.4.9. Forced internal short-circuit (cells)

This test is performed in a measurement chamber at 10ºC and 45ºC (inside the chamber) as follows:

1) Sample size

5 secondary (rechargeable) lithium cells.

2) Charge protocol

i. Charge and discharge conditions

The sample is charged in a temperature of 20ºC ± 5ºC as required by the manufacturer. The sample is then discharged at a temperature of 20ºC ± 5ºC and a constant current of 0.2 I_t (A) to a final voltage specified by the manufacturer.

ii. Storage protocol

The cell shall be stored in an ambient temperature as specified in Figure 1 for 1 – 4 hours.

iii. Ambient temperature

Table 7. Ambient temperature for cell testing

iv. Charge protocol for forced internal short-circuit test

_the cell is charged in an ambient temperature specified in Table 7 at an upper limit charge voltage and a constant current specified by the manufacturer, and continues to be charged at a constant voltage and an upper limit charging current dropped to 0.05 I_t (A).

3) Pressing coil with nickel shard

This test is performed in a temperature-controlled chamber with a special pressing device.

The moving part of the pressing device moves at a constant speed and can stop immediately upon short-circuiting.

i. Preparation

A. The chamber temperature shall be adjusted according to Table 7. Aluminum fins, the coil and nickel shard are put in the temperature-controlled chamber for 45 ± 15 minutes.

B. Remove the coil from the closed package and other devices for measuring voltage and measure the surface temperature of the coil. Place the coil under a pressed device to locate the position of the nickel shard under the pressing device.

C. Remove the insulating plate and close the chamber.

ii. Internal short-circuit

A. Compare surface temperature of the coil and Table 7 and start measuring.

B. The bottom of the moving part of the pressing device is made of nytril rubber or acrylic and placed on a stainless steel base sized 10 mm x 10 mm. Parts of the pressing device is described in Figure 2. The bottom is made of nytril rubber and used for measuring cylindrical cells. For prismatic cells, the test uses a bottom made of acrylic sized 5 mm x 5 mm (2 mm in thickness) on a plate made of nytril rubber. The fixed part moves downwards at 0.1 mm/Section to monitor the cell voltage. When voltage drops because of internal short-circuit, stop the voltage drop and hold the pressing device still in 30 seconds, then drop the pressing device. Voltage is monitor at a rate of more than 100 times per second. Short-circuit occurs when voltage drops by more than 50 mV. If pressing force reaches 800 N for a cylindrical cell and 400 N for a prismatic cell, stop the voltage drops and hold this position.

3. INSTITUTIONAL PROVISIONS

Lithium batteries used for the devices specified in Article 1.1 shall comply with provisions of this document

4. RESPONSIBILITIES

Relevant organizations and individuals shall prepare declarations of conformity of lithium batteries used for the devices specified in Article 1.1 and facilitates inspection by regulatory bodies in accordance with applicable regulations.

5. IMPLEMENTATION

5.1. Vietnam Telecommunications Authority and Provincial Services of Information and Communications shall provide guidelines and carry out management of lithium batteries used for the devices specified in Article 1.1 of this document.

5.2. Where provisions of this document is amended or replaced, new provisions shall apply./.

Bibliography

[1] IEC 61960 (06-2011): “Secondary cells and batteries containing alkaline or other non-acid electrolytes - Secondary lithium cells and batteries for portable applications”.

[2] IEC 62133 (2003): “Secondary cells and batteries containing alkaline or other non-acid electrolytes - Safety requirements for portable sealed secondary cells, and for batteries made from them, for use in portable applications”.