Week 2 Specifications of Lithium Ion Cell
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Reference to LIR18650 Datasheet Li-ion Battery Edition: NOV. 2010. Nominal or Rated capacity of a battery (in Ah) is defined as the maximum Ah a fully charged battery can deliver under certain specified conditions. These conditions include: Nominal capacity is rated capacity 2600mAh i.e 2.6Ah, under fully charged battery specified condition which is cut off or end voltage at 3.0V it can provide 2.6A for 100hour and discharged at 0.05C with 2.75V & Temp(Charge: 0 ~ 45℃ Discharge: -20 ~ 60℃). Maximun capacity with 4.20.maximum voltage and the total amount of energy contained in cell and above than the "nominal" (average) voltage 3.7V. As the battery is used, the voltage will drop lower and lower until the minimum which is around 3.0V. |
| Refer to the handling and safety guidelines, in which situation we observe the changes in dimensions and weight of a cell. |
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1) The increase in external volume (also referred to as swelling) of LIBs either arising from gas generation from electrolyte decomposition or volume expansion of electrode is not desirable. 2) (i) expansion and contraction of host materials due to lithium intercalation, (ii) electrode volume increase caused by irreversible reaction deposits, and (iii) dead volume and pressure changes within the cell case depending on battery structure and construction. 3) Crack, dislocation, deep scratch or leakage on either terminal of cell or on cell casing |
| List out various mechanical testing and standards. |
| Mechanical Test |
| Vibration (Primary and Secondary Cells and Batteries) |
| Shock (Primary and Secondary Cells and Batteries) |
| External Short Circuit (Primary and Secondary Cells and Batteries) |
| Impact (Primary and Secondary Cells) |
| Free Fall |
| Anti-vibration |
| IEC 62133 (International Electrotechnical Commission) |
| Mandated by many IEC end-device standards, IEC 62133 is the de facto standard for international compliance. UN 38.3 transportation testing (see previous section) is an integral requirement, but does not need to be repeated. |
| The standard includes four tests: |
| 2.2 Molded Case Stress |
| 3.2 External Short Circuit |
| 3.3 Free Fall |
| 3.6 Overcharging of Battery |
| Compared to the requirements of UN 38.3, these tests are relatively easy to pass. |
| UL 2054 |
| Compliance with the requirements of UL 2054 is mandated by a number of U.S. end device standards. It is a challenging standard involving roughly double the number of tests found in the UN or IEC requirements: |
| 7 electrical tests |
| 4 mechanical tests |
| 4 battery enclosure tests |
| 1 fire exposure test |
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2 environmental tests What is the discard procedure suggested? When the battery is thrown away, be sure it is non-conducting by applying vinyl tape to the (+) and (-) terminals. - When not using battery for an extended period, remove it from the equipment and store in a place |