I received my first Radio system from Arun.sreelakam, A few days back. It is a Flysky FS-T6 , This transmitter runs on 8 AA cells .
So this transmitter either need 8 AA size NiMh or Alkaline Cells Or 3S transmitter LiPo pack.
I was in a hurry to get this working , And while trying to search for a suitable battery pack for the transmitter, I found there are very few that fits in transmitter the Battery bay is Length wise bigger but Height wise It Only have 15mm .

                        As I don't really like off the shelf solutions for bigger price, I decided to make my own LiPo batter pack.
                        For that I used Old mobile phone batteries, I have a few lying around - And I selected Three Identical ones, BL-4C battery of nokia phones is the best because they are very thin.
And the BL-4C duplicate only costs 80/- For new one.

As the battery pack making is already finished I am afraid I can't upload step by step Photos, How ever for this purpose only I will make another battery pack and will post pictures along.....Stay tuned 

if you are buying try bl-5c, this one have more mah than bl4c

Hi, Akhil eatta, I haven't baught any thing I just used batteries lying around !!
Why BL-4C ? , tht's because the total size is smaller than what is that of BL-5C , Infact I tried BL-5c stacked up and found out it doesn't fit inside the battery bay of My FS-T6 as it have a single row battery bay, But if the radio has double raw battery bay, I could have used any battery I like.

And guess what, the existing pack with BL-4C (700maH)  Itself gives more than 3 Hrs, continues run.  !!!!!!!

yes yes anyway good if you have batteries already, in my old fs-ct6b(is single row 8 X AA) used BP-6M in 2P3S config  and a little tight but fit. gave me 2400Mah.

I will also try giving another 3S pack in parallel, there is a lot of space in lengthwise !!!

The duplicate BL4C or BL5C are infact LiPO instead of original Li-ion. The C rating is more than 3C for duplicate but original Li-ion is not more than 2C Discharging the cell using Transmitter is no problem (As without RF Power Module). But charging through high current charger may ruin the cell pack. Just take a little bit caution.

And surely you have removed the circuits inside cell and connect/solder directly to battery terminals. Otherwise balance charger may not sense proper during charging. If you are using separate 12 volt adapter for balance charger, use an 500mA 12 volt transformer based charger for safety.
If you have infra-red thermometer, please check temp diff of the cell pack first during charging with the charger set up you are using. If temp rise 1.5 - 2 ^OC after 5 minute of charging, you can use the charger but if the temp rise is higher, you have to be cautious, otherwise the life of the cell pack be less.

Waiting to here from you about result.

T

Quote from: KALYANPRODHAN on October 29, 2014, 12:05:28 AM
The duplicate BL4C or BL5C are infact LiPO instead of original Li-ion. The C rating is more than 3C for duplicate but original Li-ion is not more than 2C Discharging the cell using Transmitter is no problem (As without RF Power Module). But charging through high current charger may ruin the cell pack. Just take a little bit caution.
Waiting to here from you about result.

Thanks for new knowledge and the suggestions,
Of course I have removed the extra circuitry from battery.
It has been a week since I made this pack ,and I have added balance port also. But not yet tried charging this pack, as the battery voltage hasn't gone down 11.9 yet!!

I don't have an infrared thermometer ....

Overcharging beyond rated rate will generate heat and can be sensed by hands too.. after 10-15 minutes even if you use balance charger. Balance charger will drops the charging current after it attains full charge voltage. So overheat due to overcharge will not occur. But charging with over-current may generate heat even if the cell pack have not fully charged and attains it's voltage for each cell. So don't worry...

recomended charging current for BL-4C is 350ma, they use charger of 450ma and regulated. according to nokia service manual

Thanks for the Info, I will keep that in mind.

But just open any genuine NOKIA charger used for cellphone having BL4C of BL5C.
Reverse engineer the circuitry. You will laugh that the charger will be 500-800mA Capacity and the diode is of 1A (sometime it is glass-case fast diode. 0.5C charging is optimum for Li-Ion battery. But LiPO are little bit different.

checked before through my old 1100 charging terminals that ll be always below 400ma using genuine charger. if you want samples i ll take pics and send you tomorrow. and the over powered chargers are the main reason for bulging of these batteries.

Kalyan sir,

Aint that too much work fiddling with cell phone batteries when there is good alternative like normal lipo for cheaper cost available.
http://www.rcbazaar.com/products/1328-wolfpack-900mah-25c-111v.aspx
this one seems to fit the case at just 3cm wide. after removing all those casing you can save a few mm. a zippy 100mah 3S will fit perfectly after removing the outer jacket and exposing the bare cells. best thing about lipo in TX is that you dont need to worry about carrying another specific charger. I know its fun to hack things and have played a lot with lipos. but wouldnt take a chance with TX.

Ashok.P

But the thickness of the whole battery you provided is 2.8CM and For a AA battery is less than 1.5CM so we cant close cover.

and the cells may fit like in the picture

Wouldnt recommend splitting lipos. keeping them as is doesnt seems to fit the case. well, i remember seeing a 800mah turnigy lipo with my friend, that sure is slimmer than a zippy. will test and get back.

Ashok.P

I too not recommend to Split lipos.(But i did Many times)

I think the turnigy 800 mah lipo will be slimmer, but can't be slim as 1.5CM, because in 3s pack each cell must be less than 5mm thick.
please correct me I'm wrong.

Oh, you done perfectly and on right way... GRATE

And this is why guys I have to mod my own battery pack !!!
But now I found Turnigy nano tech 1450maH or somewhat pack is suitable for this transmitter ... But I have no any plans to change my battery pack, > It have been a week since I put the modded batterypack in my transmitter with fullcharge, and it still counts 11.9V. !!

I had to do similar mod because my radio battery pack died, 2S @ 4000mah Li-ion with on/off switch for charging and connection. Works Great 

2S? which is your transmitter?

Sanwa SD-10G

Gr8

Pics ?

Will upload soon.........

Pics uploaded.......