Reliance INR21700-RS50 Product Specification

Revision History

1.0 Scope

This product specification has been prepared to specify the specifications of the rechargeable lithium-ion cell to be supplied to customers (buyers) by Jiangsu Reliance Energy Tech. Co., Ltd.

2.0 Product Description and Model

2.1 Product Description: Rechargeable Lithium-ion Cell

2.2 Product Model: INR21700-RS50

3.0 Specifications

3.7 Standard discharge current

3.8 Rate charge

8A

3.9 Maximum continuous charge current

15A

3.10 Maximum continuous discharge current

70A (with 80°C temperature cut-off)

3.11 Weight

≤67.0g

3.12 Dimension

Max Diameter: 21.35mm
Max Height: 70.30mm

3.13 Operating temperature (Cell surface temperature)

Charge Temperature: 0°C~60°C
Discharge: -40°C~80°C

3.14 Storage temperature

4.0 Cell Dimension

Figure 1 illustrates the cell dimensions. The maximum diameter is 21.35mm and the maximum height is 70.30mm. A 'Prohibited Welding Area' is also indicated.

The cell height should be less than 70.30mm and the cell diameter should be less than 21.35mm.

5.0 Cell Appearance

Cells shall arrive nominally clean on all visible surfaces. There shall be no defects, such as scratch, rust, discoloration, and liquid leakage, which may adversely affect commercial value of the cell.

6.0 Test Conditions

6.1 Environmental Conditions

Unless otherwise specified, all tests stated in this Product Specification are conducted at temperature of 25±3°C and humidity of 65±20%RH.

6.2 Measuring Equipment

6.2.1 Charge and discharge equipment

Voltage precision: ±0.05%F.S
Current precision: ±0.05%F.S

6.2.2 Slide caliper

The slide caliper should have 0.01mm scale.

6.2.3 Impedance meter

AC impedance is measured by an impedance meter at 1kHz.

7.0 Characteristics

7.1 Standard Charge

Charge: 0.5C(2.5A) CCCV 4.2V, 100mA cut-off, 25±3°C.

7.2 Rate Charge

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C.

7.3 Fast Charge

Charge: 3C(15A) CCCV 4.2V, 100mA cut-off, 25±3°C.

7.4 15min Stepwise Fast Charge

Charge: 25±3°C, Charge at 10A-2min/16A-3.5min/20A-7min/10A-2.5min to 4.0Ah (80%SOC) with 4.20V protection voltage and 55°C protection temperature.

7.5 Standard Discharge Capacity

Charge: 0.5C(2.5A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest 30min.
Discharge: 0.2C(1.0A), 2.5V cut-off, 25±3°C.

Discharge Capacity: ≥4950mAh

7.6 Rate Discharge Capacity

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest 30min.
Discharge: 1.0/10/20/30/40/50/60/70A to 2.5V or 80°C cut-off, 25±3°C.

7.7 Temperature Dependence of Discharge Capacity

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest 4h at -20°C/-10°C/ 0°C/ 25°C/ 45°C.
Discharge: 40A to 2.5V or 75°C cut-off.
Percentage index of the discharge at 25±3°C at 40A is 100%.

7.8 0°C +/-10A Cycle Performance

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 0±3°C, rest 30min.
Discharge: 10A to 2.5V or 75°C cut-off, 0±3°C.
Cycle 200 times.

200 Cycles Capacity Retention: ≥80%

7.9 -10°C +/-10A Cycle Performance

Charge: 3A CCCV 4.2V, 100mA cut-off, -10±3°C, rest 30min.
Discharge: 10A to 2.5V or 75°C cut-off, -10±3°C.
Cycle 50 times. (Remark: we're not responsible for cell cycle life and cell safety when charging the cell below 0°C.)

50 Cycles Capacity Retention: ≥80%

7.10 RT +8/-40A Cycle Performance

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest 30min.
Discharge: 40A to 2.5V or 75°C cut-off, 25±3°C.
Cycle 400 times.

400 Cycles Capacity Retention: ≥60%

7.11 RT +15/-30A Cycle Performance

Charge: 3C(15A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest 30min.
Discharge: 30A to 2.5V or 75°C cut-off, 25±3°C.
Cycle 400 times.

400 Cycles Capacity Retention: ≥60%

7.12 Storage Characteristic

Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C.
Storage: 60±3°C, 30 days.
Discharge: 2.5A to 2.5V cut-off, 25±3°C, defined as retained capacity.
Charge: 1.6C(8A) CCCV 4.2V, 100mA cut-off, 25±3°C, rest for 10min
Discharge: 2.5A to 2.5V cut-off, 25±3°C, defined as recovered capacity.

Retained Capacity/Initial Capacity: ≥80%
Recovered Capacity/Initial Capacity: ≥90%

7.13 Status of the Cell as of Ex-factory

The cell should be shipped between 3.46V and 3.52V.

8.0 Mechanical Characteristics

8.1 Vibration Test

According to the UN38.3 standard, the test sample cell is charged at a rate of 8A (8A CCCV at 8A to 4.20V, with a cutoff of 100mA) at 25±3°C. The cell is then installed on the table of the vibration table with fixtures, and radial and axial vibrations are performed along the cell for 15 minutes (7Hz→200Hz→7Hz) for 12 repetitions, totaling 3 hours. (Sweep vibration: accelerate from 7Hz to 18Hz with an acceleration of 1G, maintain a vibration amplitude of 0.8mm and increase the frequency to achieve an acceleration of 8G, maintain an acceleration of 8G to increase the frequency to 200Hz).

Criteria: No leakage, with less than 10% of OCV drop.

8.2 Drop Test

According to the IEC62133 standard, the test sample cell is charged at a rate of 8A (CCCV at 8A to 4.20V, with a cutoff of 100mA) at 25±3°C, and dropped freely from a height of 1m in each direction (X, Y, Z) to the concrete ground once.

Criteria: No fire, no explosion.

8.3 Crush Test

According to the UL1642 standard, the test sample cell is charged at a rate of 8A (CCCV at 8A to 4.20V, with a cutoff of 100mA) at 25±3°C. The cell is then subjected to compression between two flat planes, with its circular face parallel to the plane of the compression device, until the pressure reaches 13±1kN (3000 ±224lbs). Once the force reaches its maximum, it is released.

Criteria: No fire, no explosion.

9.0 Safety Test

9.1 2C 6V Overcharge Test

According to the IEC62133 standard, the test sample cell is discharged to 2.5V at a constant current of 1.0A. The cell is then overcharged at 10A to 6V. The cell is monitored for 1h.

Criteria: No fire, no explosion.

9.2 Forced-Discharge Test

According to the IEC62133 standard, the test sample cell is discharged to 2.5V at a constant current of 1.0A. The cell is then discharged at 5.0A for 90min. The cell is monitored for 1h.

Criteria: No fire, no explosion.

9.3 Short-circuit Test

According to the UL1642 standard, the test sample cell is charged at a rate of 8A (CCCV at 8A to 4.20V, with a cutoff of 100mA) at 25±3°C, then short-circuit the positive and negative for 10min with the copper wire (resistance: 80±20mΩ). The cell is monitored for 1h.

Criteria: No fire, no explosion.

9.4 Heating Test

According to the UL1642 standard, the test sample cell is charged at a rate of 8A (CCCV at 8A to 4.20V, with a cutoff of 100mA) at 25±3°C, and then transferred into a circulating air oven. The temperature of the oven is raised at a rate of 5°C per minute to a temperature of 130°C±2°C and remain for 10min at that temperature.

Criteria: No fire, no explosion.

10.0 Proper Use and Handling of Lithium Ion Cells

Before using lithium-ion cell, read the document provided by Jiangsu Reliance Energy Tech. Co., Ltd.

10.1 Charge

10.1.1 Charge Current

Charge current should be less than the maximum value specified in the Specifications.

10.1.2 Charge Voltage

Charging shall be done by voltage less than that specified in the Specifications.

10.1.3 Charge Temperature

Cells shall be charged according to the Temperature Condition specified in the Specifications. Charging at subzero temperature shall be prohibited.

10.1.4 Prohibition of Charge

It is prohibited to charge the cells which are used for single with less than 1.5V voltage.
It is prohibited to charge the cells which are used for series with less than 2.0V voltage.

10.1.5 Prohibition of Reverse Charge

Reverse charge is prohibited. Cells shall be connected correctly. The polarity has to be confirmed before wiring. If a cell is connected improperly, the cell cannot be charged. Simultaneously, the reverse charging may cause damage to the cell which may lead to degradation of cell performance and damage the cell safety, and could cause heat generation or leakage.

10.1.6 Avoiding Floating Charge

Floating charge (continuous constant voltage control by the end of charging step) for a long term shall be avoided.

10.2 Discharge

10.2.1 Discharge Current

The cells shall be discharged at less than the maximum discharge current specified in the Specifications. High discharging current may reduce the discharge capacity significantly or cause over-heating.

10.2.2 Discharge Temperature

Cells shall be discharged according to the Temperature Condition specified in the Specifications.

10.2.3 Over-discharge

It should be noted that cells would be at an over-discharged status due to self-discharge characteristics if they were not used for a long time. In order to prevent over-discharging, Cells shall be charged periodically to maintain the voltage between 3.45V and 3.95V. Over-discharging may cause the loss of cell performance, characteristics, or battery functions.

10.3 Storage

The cell should be stored within a range of temperatures specified in the product specification.
During storage, the voltage will drop and the recoverable capacity will be lost little by little with the time.
The cell voltage should be kept in the range of 3.45V to 3.95V by charging the cells if the cells are stored more than 3 months.

10.4 Cycle Life

The cell can be charged/discharged repeatedly up to the cycle life with a certain level of capacity specified in the production specification.
Cycle life may be determined by conditions of charging, discharging, operating temperature and storage.

10.5 Protection Function Requirements for Battery and Host Device

Battery pack and host device shall be designed with the following protection functions to make sure that the cells would be under safe usage conditions: Over-charge protection; Over-discharge protection; Over current protection; Over-heat protection; Short circuit protection.

10.5.1 Over-charge Protection

The host device and battery pack shall be designed to indefinitely withstand the maximum voltage from the adapter, under a single fault condition, to prevent a cascading failure through the system to the battery pack and/or cell.

10.5.2 Over-discharge Protection

When the voltage of any cell in a battery pack is lower than 2.5V, over-discharge protection function shall work and stop discharging to prevent the cells from over-discharge. It is recommended that the dissipation current of PCM shall be less than 1.0uA. The voltage of each cell in a battery pack shall be monitored and current shall be controlled by the PCM at all times.

10.5.3 Over-current Protection

In case the charge current is over the limitation specified in Specifications, the charging must be cut off. The battery pack shall have at least one over current protection circuitry or devices designed to meet the specification to avoid the cell from becoming charged with current greater than the Specifications.
The host device shall be designed to indefinitely withstand the maximum current from the adapter, under a single fault condition, to prevent a cascading failure through the system to the battery pack and/or cell.

10.5.4 The Requirements to the Components of Protection Circuit

Cells, components, and materials used in the battery pack shall meet the minimum and maximum temperature requirements with adequate margin. Protection circuit components (excluding thermal devices designed to activate at specific temperatures) shall be applied for a minimum operating range of -25 °C to +85 °C.

10.5.5 Over-temperature Protection

The battery pack or host device shall contain at least one thermal protection device or mechanism independent of internal cell devices or mechanisms. For a thermistor type temperature protection circuit, all packs of the same model shall have the same voltage to temperature translation (acceptable tolerance no more than ±10%), with consideration for any temperature lag over time.
During charge and discharge, the temperature of the cell shall be monitored. When temperature limitations are exceeded, action shall be taken to mitigate hazards. Action should include shutdown, or disabling of charging, or other protective action. The action may be taken by the battery pack and/or host.

10.5.6 The Limitation of Charge Time

In order to prevent abnormal cells or battery packs, charge time shall be limited according to the Specifications. When time limitations are exceeded, action shall be taken by the host device or the battery pack to shut down or disable the charging.

10.5.7 Pre-charge Function

The system shall not initiate normal charging if the battery voltage is below the over-discharge protection voltage defined in the Specifications. In this case, the system may support a pre-charging function to bring the battery voltage above the required threshold. The recommended pre-charge procedure is as below: the cell battery pack charging shall start with a low current (0.02Cmin mA) for approximately 30 minutes before rapid charging starts. The normal charging shall be started after the (individual) cell voltage has been reached above 3V within approximately 30 minutes that can be determined with the use of an appropriate timer for pre-charging. In case the (individual) cell voltage does not rise to 3V within the pre-charging time, then the charger shall have functions to stop further charging and display that the cell/pack is at an abnormal state.

10.5.8 The Other Requirements to Main Device Designation

If the source of the fault is in the host device, it shall not disable the safety features inside the battery pack(s).
The charging system, or any part of the host device, shall not disable or override the safety features inside the battery pack(s).

10.6 Notice for Designing Battery Pack

10.6.1 Pack Design

Battery pack should have sufficient strength to make sure the cell inside is protected from mechanical shock.
No sharp edge components should be inside the pack containing the battery cells.
Allowances shall be made for cell and battery pack dimensional tolerance and changes throughout the product lifetime.

10.6.2 Cell Fixing

Movement of cell in the battery pack should not be allowed.
Short circuit of cell in a battery pack or Host Device should not be allowed: Enough insulation layers between wiring and the cell shall be used to maintain extra safety protection. The battery pack or host device shall be structured without any potential short circuit, which may cause generation of smoke or firing.

10.7 Transportation

The cell capacity is approximately at 30% of charging for delivery. It is not specified more than 30% capacity remaining at customer due to self-discharge.
During transportation, keep the cell from severe vibrations, impacts, and exposure to sunlight and rain.

11.0 Safety Instruction

11.1 Danger

• Use dedicated charger.
• Use or charge the battery only in the dedicated application.
• Don't charge the battery by an electric outlet directly.
• Don't charge the battery reversely.
• Don't leave the battery near the fire or a heated source.
• Don't throw the battery into the fire.
• Don't leave, charge or use the battery in a car or similar place where inside of temperature may be over 60°C.
• Don't immerse, throw, wet the battery in water / seawater.
• Don't store the battery in a pocket or a bag together with metallic objects such as keys, necklaces, hairpins, coins, or screws.
• Don't short circuit (+) and (-) terminals with metallic object intentionally.
• Don't pierce the battery with a sharp object such as a needle, screw drivers.
• Don't heat partial area of the battery with heated objects such as soldering iron.
• Don't hit with heavy objects such as a hammer, weight.
• Don't step on the battery and throw or drop the battery on the hard floor to avoid mechanical hock.
• Don't disassemble the battery or modify the battery design including electric circuit.
• Don't solder on the battery directly.
• Don't use seriously scared or deformed battery.
• Don't put the battery into a microwave oven, dryer, or high-pressure container.
• Don't use or assemble the battery with other makers' batteries, different types and/or models of batteries such as dry batteries, nickel-metal hydride batteries, or nickel-cadmium batteries.
• Don't use or assemble old and new batteries together.

11.2 Warning

• Stop using the battery if the battery becomes abnormally hot, ordor, discoloration, deformation, or abnormal conditions is detected during use, charge, or storage.
• Keep away from fire immediately when leakage or foul odors are detected. If liquid leaks onto your skin or cloths, wash well with fresh water immediately.
• If liquid leaking from the battery gets into your eyes, don't rub your eyes and wash them with clean water and go to see a doctor immediately.
• If the terminals of the battery become dirty, wipe with a dry cloth before using the battery.
• Cover terminals with proper insulating tape before disposal.

11.3 Caution

• Keep the battery away from babies and children to avoid any accidents such as swallow.
• If younger children use the battery, their guardians should explain the proper handling method and precaution before using.
• Before using the battery, be sure to read the user's manual and precaution of its handling.
• Before using charger, be sure to read the user's manual of the charger.
• Before installing and removing the battery from application, be sure to read user's manual of the application.
• Replace the battery when using time of battery becomes much shorter than usual.
• Cover terminals with insulating tape before proper disposal.
• If the battery is needed to be stored for an long period, battery should be removed from the application and stored in a place where humidity and temperature are low.
• While the battery is charged, used and stored, keep it away from object materials with static electric chargers.

Contact Information

If you have any questions regarding the cell and application, please contact the following address:

Jiangsu Reliance Energy Tech. Co., Ltd.

Add: No. 1289, Huanghe West Road, Xinbei District, Changzhou City, Jiangsu, P.R. China

Tel: +86 0519 69887551

P.C.: 213002