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: Maximal charging voltage

4,2V± 0,03V / cell Charging current 1C is standard,

1÷ 3C for „HD“ and “SHD” types can be use (no full charge cycle)

Temperature of charging cells between 0°C up to 45°C

Never charge over pole battery

Battery discharging:

Discharging current 2 ÷ 3C for standard types, 5C, 8C or 10C for „HD“, types and 15 – 20C for SHD types.

Temperature of discharging cells between -10°C up to +60°C.

minimum discharging voltage 3,0V / cell.

Short circuit can damage cells.

Discharge 1250 SHD battery

Service connector SCA_5

pack 3S with service connector

Instructions for assembly and operation: 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)

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.

Use connection boards SP xx and SS xx when connecting the battery to packs – this will eliminate chance of damaging the battery

Glue the battery together using both sides tape – thin 5mm strips on ends Never fasten the battery in model using their nodes! Use only very flexible silicon isolated wires as input wires Charge only in chargers designed for Li-Pol cells l!! In packs assemble only cells with the same capacity, same type and from the same manufacturer 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.

There is no memory effect. It is possible to start charging batteries no matter how discharged (in the allowed working voltage range).

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.

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.

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:

All type of Lipol cell are provided in serial packs of 2, 3 and 4 or in any serial parallel combination. 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.

standard pack 3S

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: 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.

Type of the cell

Ord

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g nu

mbe

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cap

acity

[mAh

]

Mid

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harg

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Con

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Max

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No. Basic electric parameters mechanical parameters

Simple Lipol cells KOKAM

K 3300 3~4C 0567 3300 3,7 11,5 -- 95,0 64,0 5,4 66,0

K 145 HD 8C 0553 145 3,7 1,1 2,2 27,5 20,5 4,5 3,5 K 720 HD 8C 0583 720 3,7 5,5 11,0 58,5 33,5 4,0 16,0

K 1500 HD 8C 0584 1500 3,7 12,0 24,0 70,5 37,5 6,7 32,5

K 640 SHD 15C 0588 640 3,7 9,5 19,0 58,5 33,5 4,4 17,0 K 910 SHD 15C 0589 910 3,7 13,5 27,0 59,0 33,5 6,2 23,0

K 1250 SHD 15C 0587 1250 3,7 18,5 37,0 74,0 43,0 5,4 34,0 K 2000 SHD 15C 0586 2000 3,7 30,0 60,0 74,0 43,0 8,2 51,0

K 360 SHD 20C 0582 360 3,7 7,0 14,0 52,0 33,5 3,0 11,0 K 730 SHD 20C 0590 730 3,7 14,5 29,0 59,0 33,5 5,4 21,0

K 3200 SHD 20C 0591 3200 3,7 64,0 128,0 131,0 43,5 7,6 82,0

Simple Lipol cells E-Tech

E 1200 HD 10C 0585 1200 3,7 12,0 -- 60,0 34,0 6,0 25,0 E 1250 HD 10C 0592 1250 3,7 12,5 -- 60,0 34,0 7,0 27,0 E 1700 HD 10C 0593 1700 3,7 17,0 -- 65,0 39,0 8,5 40,0

service connector - detail

Pins for PCB with housing

cell 1

cell 2

cell 3

cell 4

Type of the cell

Ord

erin

g nu

mbe

r

cap

acity

[mA

h]

Mid

dle

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disc

harg

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volta

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]

Con

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A]

Max

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[A

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leng

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[mm

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wid

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mm

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gram

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No. Basic electric parameters mechanical parameters

Battery packs

K 360 SHD 20C 2S 1530 360 7,4 7,0 14,0 52,0 33,5 ~7 ~23 K 360 SHD 20C 3S 1531 360 11,1 7,0 14,0 52,0 33,5 ~11 ~34 K 360 SHD 20C 4S 1545 360 14,8 7,0 14,0 52,0 33,5 ~15 ~45 K 640 SHD 15C 2S 1547 640 7,4 9,5 19,0 58,5 33,5 ~9 ~35 K 640 SHD 15C 3S 1548 640 11,1 9,5 19,0 58,5 33,5 ~14 ~53 K 640 SHD 15C 4S 1549 640 14,8 9,5 19,0 58,5 33,5 ~19 ~70 K 720 HD 8C 2S 1532 720 7,4 5,5 11,0 58,5 33,5 ~8 ~34 K 720 HD 8C 3S 1533 720 11,1 5,5 11,0 58,5 33,5 ~13 ~51 K 720 HD 8C 4S 1546 720 14,8 5,5 11,0 58,5 33,5 ~18 ~68 K 730 SHD 20C 2S 1547 730 7,4 14,5 29,0 59,0 33,5 ~12 ~43 K 730 SHD 20C 3S 1548 730 11,1 14,5 29,0 59,0 33,5 ~18 ~64 K 730 SHD 20C 4S 1549 730 14,8 14,5 29,0 59,0 33,5 ~24 ~86 K 910 SHD 15C 2S 1550 910 7,4 13,5 27,0 59,0 33,5 ~13 ~48 K 910 SHD 15C 3S 1551 910 11,1 13,5 27,0 59,0 33,5 ~19 ~72 K 910 SHD 15C 4S 1552 910 14,8 13,5 27,0 59,0 33,5 ~26 ~96

K 1250 SHD 15C 2S 1542 1250 7,4 18,5 37,0 74,0 43,0 ~12 ~70 K 1250 SHD 15C 3S 1543 1250 11,1 18,5 37,0 74,0 43,0 ~18 ~105 K 1250 SHD 15C 4S 1544 1250 14,8 18,5 37,0 74,0 43,0 ~24 ~140 K 1500 HD 8C 2S 1534 1500 7,4 12,0 24,0 70,5 37,5 ~14 ~68 K 1500 HD 8C 3S 1535 1500 11,1 12,0 24,0 70,5 37,5 ~21 ~102 K 1500 HD 8C 4S 1541 1500 14,8 12,0 24,0 70,5 37,5 ~28 ~136 K 2000 SHD 15C 2S 1534 2000 7,4 30,0 60,0 74,0 43,0 ~17 ~104 K 2000 SHD 15C 3S 1539 2000 11,1 30,0 60,0 74,0 43,0 ~26 ~156 K 2000 SHD 15C 4S 1540 2000 14,8 30,0 60,0 74,0 43,0 ~35 ~208 K 3200 SHD 20C 2S 1553 3200 7,4 64,0 128,0 131,0 43,5 ~16 ~168 K 3200 SHD 20C 3S 1554 3200 11,1 64,0 128,0 131,0 43,5 ~26 ~252 K 3200 SHD 20C 4S 1555 3200 14,8 64,0 128,0 131,0 43,5 ~35 ~336

E 1200 HD 10C 2S 1536 1200 7,4 12,0 -- 60,0 34,0 ~13 ~52 E 1200 HD 10C 3S 1537 1200 11,1 12,0 -- 60,0 34,0 ~20 ~78 E 1200 HD 10C 4S 1556 1200 14,8 12,0 -- 60,0 34,0 ~27 ~104 E 1250 HD 10C 2S 1557 1250 7,4 12,5 -- 60,0 34,0 ~15 ~56 E 1250 HD 10C 3S 1558 1250 11,1 12,5 -- 60,0 34,0 ~22 ~84 E 1250 HD 10C 4S 1559 1250 14,8 12,5 -- 60,0 34,0 ~30 ~112 E 1700 HD 10C 2S 1560 1700 7,4 17,0 -- 65,0 39,0 ~18 ~82 E 1700 HD 10C 3S 1561 1700 11,1 17,0 -- 65,0 39,0 ~27 ~143 E 1700 HD 10C 4S 1562 1700 14,8 17,0 -- 65,0 39,0 ~36 ~164