KOKAM Lithium Polymer Batteries
Modern lithium batteries are nowadays one of the most perspective sources in the area of small
currents ranging from 10 to 40A. If at least basic rules for usage and operation are kept, lithium
batteries are safe and may be successfully used in model drives. Some types of „SHD“ batteries have
extremely small inner resistance (they can beat even pushed NiMH cells 3,3Ah.The requirements for
obtaining the best performance are suitable charger (e.g. AQC 4, AQC 4F) and appropriate capacity of
batteries concerning discharging currents. Manufacturer guarantees discharging by currents up to 8 –
10C for “HD” (hard) marking batteries and 15 – 20C for “SHD” (super hard) marking batteries. It is, for
example, 64A from one cell Kokam 3200 mAh / 20C ! Batteries may be connected serial - parallel. It
is no problem have the battery for 40 ÷ 120A with voltage range 7 ÷ 40V with capacity 6 up to 12 Ah !
Outstanding batteries of south Korean company KOKAM have the following features:
Some of the Kokam cells
Some of the E-Tech cells
Lipol batteries advantages:
•
•
•
•
•
•
•
the positive Aluminum node is nickel tabbed for easy soldering
no inner fuses (inner resistance of batteries is therefore not unnecessarily rising)
average discharging voltage ca 3,6V per cell
impedance is given for frequency of 1kHz and ca half discharged batteries
number of cycles for current of 0,5C is 500 and is given for lowering the capacity to 80%
after 100 cycles by a full current(full load) capacity going down about 15 ÷ 20%
have not “memory” effect
Battery charging:
ƒ Maximal charging voltage
4,2V± 0,03V / cell
ƒ Charging current 1C is standard,
1÷ 3C for „HD“ and “SHD” types
can be use (no full charge cycle)
ƒ Temperature of charging
cells between 0°C up to 45°C
ƒ Never charge over pole battery
Battery discharging:
ƒ Discharging current 2 ÷
3C for standard types,
5C, 8C or 10C for „HD“,
types and 15 – 20C for
SHD types.
ƒ Temperature of
discharging cells between
-10°C up to +60°C.
ƒ minimum discharging
voltage
3,0V / cell.
ƒ Short circuit can damage
cells.
Discharge 1250 SHD battery
Instructions for assembly and operation:
ƒ Solder quickly wires (or connection boards SS xx or SP xx) to outputs of accumulators - positive
node may be soldered on one side only !!! – from the same side as are markings on batteries.
Prevent any shortcut of the wires. Use only quality solder and no aggressive fusing agents
– such as colophony, etc. or soft solder with fusing agent inside. The best are soft solders with
added Ag (for example Sn62,5/Pb36/Ag1,5)
ƒ To protect battery nodes from being ripped out of battery the wires soldered to PCB of battery should
then fastened (for example with a duality tape) to battery.
ƒ Use connection boards SP xx and SS xx when connecting the battery to packs – this will
eliminate chance of damaging the battery
ƒ Glue the battery together using both sides tape – thin 5mm strips on ends
ƒ Never fasten the battery in model using their nodes!
ƒ Use only very flexible silicon isolated wires as input wires
ƒ Charge only in chargers designed for Li-Pol cells l!!
ƒ In packs assemble only cells with the same capacity, same type and from the same manufacturer
ƒ It is necessary that battery that will be assembled in one pack are all the same quality and are
charged to the same voltage – this can be easily done: first charge each battery separately. It is
not recommended to put battery that have been used for some time with new battery into one
pack. The best is to put together battery that have been chosen for the same capacity and
inner resistance.
ƒ There is no memory effect. It is possible to start charging batteries no matter how discharged (in
the allowed working voltage range).
ƒ If you connect two batteries parallel you will get double the capacity and may draw double
currents. Number of parallel connected batteries in not limited.
ƒ When connecting cell in serial the obtained voltage of such pack is higher than that of a single cell.
However, maximal capacity and currents are then same for both – a pack or one cell.
ƒ If the cells are connected in serial parallel – higher voltage as well as capacity and currents is obtained.
First connect cell that are supposed to be in parallel. Then connect them in parallel.
Battery packs:
ƒ All type of Lipol cell are provided in serial packs of 2, 3 and 4 or in any serial parallel combination.
ƒ In Standard packs (serial 2, 3and 4), inner wires can also be equipped with a service connector which
enables to ensure the same voltage in all cells. Service connector is a specialized non-interchangeable
type (it is not possible to reverse polarity) with a mechanical lock against an unwanted rip out. A highly
endurable industrial kinds of wires (endurable against heat and mechanical destructions) are used to
connect witch the service connector.
Service connector SCA_5
standard pack 3S
pack 3S with service
connector
Service connectors:
You can buy simple service connector, with 3 cables (for 2 cells), with 4 cables (for 3 cells) and with 5 cables
(for 4 cells). You can buy simple pins part for PCB also.
Recommended circuit:
service connector - detail
cell 1
cell 2
cell 3
cell 4
Pins for PCB with housing
No.
Basic electric parameters
weight [grams]
width [mm]
wide [mm]
length
[mm]
Max. current
[A]
Continuous
current [A]
Middle of
discharging
voltage [V]
capacity [mAh]
Type of the cell
Ordering number
Note: for 2 and 3 cells is not assembly cables for cell 4, and/or cell 3. Cables for cell 1 and cell 2 is assembly
already.
mechanical parameters
Simple Lipol cells KOKAM
K 3300
3~4C
0567
3300
3,7
11,5
--
95,0
64,0
5,4
66,0
8C 0553
8C 0583
8C 0584
145
720
1500
3,7
3,7
3,7
1,1
5,5
12,0
2,2
11,0
24,0
27,5
58,5
70,5
20,5
33,5
37,5
4,5
4,0
6,7
3,5
16,0
32,5
K 145
K 720
K 1500
HD
HD
HD
K 640
K 910
K 1250
K 2000
SHD
SHD
SHD
SHD
15C
15C
15C
15C
0588
0589
0587
0586
640
910
1250
2000
3,7
3,7
3,7
3,7
9,5
13,5
18,5
30,0
19,0
27,0
37,0
60,0
58,5
59,0
74,0
74,0
33,5
33,5
43,0
43,0
4,4
6,2
5,4
8,2
17,0
23,0
34,0
51,0
K 360
K 730
K 3200
SHD
SHD
SHD
20C
20C
20C
0582
0590
0591
360
730
3200
3,7
3,7
3,7
7,0
14,5
64,0
14,0
29,0
128,0
52,0
59,0
131,0
33,5
33,5
43,5
3,0
5,4
7,6
11,0
21,0
82,0
3,7
3,7
3,7
12,0
12,5
17,0
----
60,0
60,0
65,0
34,0
34,0
39,0
6,0
7,0
8,5
25,0
27,0
40,0
Simple Lipol cells E-Tech
E 1200
E 1250
E 1700
HD
HD
HD
10C
10C
10C
0585
0592
0593
1200
1250
1700
No.
weight [grams]
width [mm]
wide [mm]
length
[mm]
Max. current
[A]
Continuous
current [A]
Middle of
discharging
voltage [V]
capacity [mAh]
Ordering number
Type of the cell
mechanical parameters
Basic electric parameters
Battery packs
K 360
K 360
K 360
K 640
K 640
K 640
K 720
K 720
K 720
K 730
K 730
K 730
K 910
K 910
K 910
K 1250
K 1250
K 1250
K 1500
K 1500
K 1500
K 2000
K 2000
K 2000
K 3200
K 3200
K 3200
SHD
SHD
SHD
SHD
SHD
SHD
HD
HD
HD
SHD
SHD
SHD
SHD
SHD
SHD
SHD
SHD
SHD
HD
HD
HD
SHD
SHD
SHD
SHD
SHD
SHD
20C
20C
20C
15C
15C
15C
8C
8C
8C
20C
20C
20C
15C
15C
15C
15C
15C
15C
8C
8C
8C
15C
15C
15C
20C
20C
20C
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
2S
3S
4S
1530
1531
1545
1547
1548
1549
1532
1533
1546
1547
1548
1549
1550
1551
1552
1542
1543
1544
1534
1535
1541
1534
1539
1540
1553
1554
1555
360
360
360
640
640
640
720
720
720
730
730
730
910
910
910
1250
1250
1250
1500
1500
1500
2000
2000
2000
3200
3200
3200
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
7,0
7,0
7,0
9,5
9,5
9,5
5,5
5,5
5,5
14,5
14,5
14,5
13,5
13,5
13,5
18,5
18,5
18,5
12,0
12,0
12,0
30,0
30,0
30,0
64,0
64,0
64,0
14,0
14,0
14,0
19,0
19,0
19,0
11,0
11,0
11,0
29,0
29,0
29,0
27,0
27,0
27,0
37,0
37,0
37,0
24,0
24,0
24,0
60,0
60,0
60,0
128,0
128,0
128,0
52,0
52,0
52,0
58,5
58,5
58,5
58,5
58,5
58,5
59,0
59,0
59,0
59,0
59,0
59,0
74,0
74,0
74,0
70,5
70,5
70,5
74,0
74,0
74,0
131,0
131,0
131,0
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
33,5
43,0
43,0
43,0
37,5
37,5
37,5
43,0
43,0
43,0
43,5
43,5
43,5
~7
~11
~15
~9
~14
~19
~8
~13
~18
~12
~18
~24
~13
~19
~26
~12
~18
~24
~14
~21
~28
~17
~26
~35
~16
~26
~35
~23
~34
~45
~35
~53
~70
~34
~51
~68
~43
~64
~86
~48
~72
~96
~70
~105
~140
~68
~102
~136
~104
~156
~208
~168
~252
~336
E 1200
E 1200
E 1200
E 1250
E 1250
E 1250
E 1700
E 1700
E 1700
HD
HD
HD
HD
HD
HD
HD
HD
HD
10C
10C
10C
10C
10C
10C
10C
10C
10C
2S
3S
4S
2S
3S
4S
2S
3S
4S
1536
1537
1556
1557
1558
1559
1560
1561
1562
1200
1200
1200
1250
1250
1250
1700
1700
1700
7,4
11,1
14,8
7,4
11,1
14,8
7,4
11,1
14,8
12,0
12,0
12,0
12,5
12,5
12,5
17,0
17,0
17,0
----------
60,0
60,0
60,0
60,0
60,0
60,0
65,0
65,0
65,0
34,0
34,0
34,0
34,0
34,0
34,0
39,0
39,0
39,0
~13
~20
~27
~15
~22
~30
~18
~27
~36
~52
~78
~104
~56
~84
~112
~82
~143
~164