LI-ION batteries

Li-Ion (Lithium-Ion) is the most common cell for mobile applications – Ranging from mobile phones to usage of space applications.  These cells are very easy to come-by, the problem is assembling them correctly, with the proper electronics & control and verifying their performance.

Why do we really like Li-Ion projects When we do not necessarily recommend to use Li-Ion cells
  • Because Li-Ion is usually cost effective, so we can supply a relatively cheap solution.
  • When our customer asks for very high currents.  The Li-Ion has relatively high Internal Resistance and therefor drops voltage in high currents
  • Because Li-Ion from large companies are very reliable
  • When our customer wants to maximize capacity in given volume.  Li-Ion is common in a few basic dimensions.  Most of the times cannot reach 100% volume usage.
  • Because Li-Ion cells are available.  Most of the brands are easy to purchase.
  • When our customer wants minimum weight.  Li-Ion Polymer (Pouch) is better than L-Ion
  • Because Li-Ion has also very reliable and cost effective brands.
  • When our customer has an application operating in low temperature (again, that IR)
  • Because the majority of Li-Ion (from large companies) have all the certifications needed
  •  
Basic features
  • Easy to assemble – short proto-type time.
  • Environmentally Friendly – No cadmium, mercury or other heavy metals.
  • High Energy Density – ~245 Wh/Kg
  • Discharge currents: 2C max
  • Long Cycle Life – Charge and discharge can be repeated over 500 times (and >800 in most times) with stable discharge voltage during normal operation.
Performances of High end cells
  • Cells for High Energy Density per Mass: up to 260 Wh/Kg
  • Cells for High Energy Density per Volume: up to 760 Wh/Liter
  • Cells for High discharge currents up to 30A
  • Cells for Up to 2000 cycles
High end cells:
  • Cells for High Energy Density per Volume: up to 760 Wh/Liter
  • Cells for High discharge currents up to 30A
  • Cells for Up to 2000 cycles

 

Li-Ion standard Cells

Samsung ICR18650-26

3.7V

2600

18.4

65.0

2C

 

47.0

Panasonic NCR18650A

3.6V

3100

18.6

65.2

2C

 

45.5

Panasonic NCR18650B

3.6V

3350

18.3

65.1

2C

 

47.5

Panasonic NCR18650PF

3.6V

2900

18.6

65.2

10A

18A

47.0

LG INR18650-MJ1

3.635V

3500

18.5

65.2

10A

 

49.0

Samsung INR18650-30Q

3.6V

3000

18.4

65.0

15A

 

48.0

Samsung 21700-48G

3.6V

4800

21

70.5

9.6A

 

67.4

Item P.N.

Voltage

Capacity [mAh]

Dimensions [mm]

C-Rate / Discharge

Weight [gram]

Ø max

L max

Max

Peak

Typical assemblies:

 Li-Ion 25.9V, 60.9Ah for UGV  Li-Ion 7.4V, 5.2Ah for communication equipment
Li-Ion 25.9V, 60.9Ah Li-Ion 7.4V, 5.2Ah