What are the best lightweight battery plugs to use with batteries such as these? I think the micro-JST/pico plugs would be good, but as far as I can tell hobbyking don't sell them on their own- only in parallel adapters and even then you don't get any males.
I couldnot find the exact battery type for the micro but if you have the orignal then just match the diamensions of the 2 cells and see if it will fit the battery compartment and the maheven if it's slightly higher then it's ok
I´m not sure about it´s chemistry.
But I use them in a 2S configuration on my micro cars and they have a good discharge curve, holding voltage until the end and not saging lower when I hit the trhottle.
The thing is here I plan on using them potted in epoxy and have my own circuit connected handling charge, discharge and protection. I would like to know the chemistry so i can have a decent approximation of the cut-off voltage I need in order to retain a certain capacity in the battery (for longevity). For example, with some types you can approximate that at 3.5V you'll still have 20% left in the battery. If these batteries were the same, I could take that value as my safety cutoff to stop the discharge.
Potted in epoxy? Could there be any potential problem with doing that should the lipo 'puff' and/or decide to destroy itself as they occasionally do? Would the epoxy not permit the heat generated during use to dissipate as it should?
*WTWUK "Could there be any potential problem with doing that should the lipo 'puff' and/or decide to destroy itself as they occasionally do?"
That is exactly why I need to make absolutely sure it will never go into zones of operation that will stress the battery. This is not your standard RC application. I use relatively low currents, 0.1C discharge and 0.1-0.7C charge and I have a purpose built circuit that will charge to a max of 4.15V and cutoff the battery at 3.6V until the charger is present again.
*WTWUK "Would the epoxy not permit the heat generated during use to dissipate as it should?"
No, the heat will not be carried away as easily as if the battery was in free air. Hence I have to be really careful with heat management (ex. lowering charge/discharge currents).
iv always charged mine at 1c. never trusted turnigys saying of 2c. charge one of my other turnigys before at the stated 2c and the pack come of the charger hot. if your getting a bunch of these you can always hook them up in parrallel on the charger so you can charge them all at the same time
Hello, I am new at this, I would really appreciate it if someone can give some advise on how to charge the batteries.If I joint three of them in parallel, can someone tell me how do I charge it?. 1C of 720mAh = 0.7 Amp? and If I joint them in series, is it also the same 0.7 Amp?
Hi. If you join them in series, you will get 3S1P bat with 11.1V and 720mAmps: Charge 1C=0.7A. If you join them in parallel, you will get 1S3P bat with 3.7V and 2160mAmps: teoretically 1C=2A but you have to monitor each cell not to overcharge it. Regards
Not only is that advice wrong, it's dangerous. 3 240 mAh batteries in parallel will give you one battery with a nominal voltage of 3.7 and a capacity of 720 mAh. A 1C charge would be 0.7 amps. 3 of these cells in series would give you a pack voltage of 11.1 with a capacity of 240 mAh. A 1C charge for that pack would be 0.24 amps.
Based on my experience with 6 of such lipos, the capacity varies. My advice is to charge them individually and then connect them in parallel so as to 1) avoid overcharging the lipos and 2) give you flexibility to change the weaker/damage lipo.
Hi, in my experience this cells should be charged at 1C=0.2A so if you have 3 in parallel charge them at 0.6A, if you have 3 in series charge them ay 0.2A
Remember in parallel the voltage is equal in all the cells but the current is the current of 1 cell multiplied by the number of cells, in series the current is equal in every cell but the voltage of the full package is the voltage of 1 cell multiplied by the numer of cells
I have 3 of these same lipo cells, I would recommend charging in parallel and i would charge them at .6mah. I say .6mah because the cells hold closer to 190mah on a full cycle. with all three cells charging on a parallel circut you would follow recommend 1c charging for all cells.
I would suggest some very small connector. You can use even a servo wire. To put 2 batteries into series, you have to solder of the first battery to the - of the second battery and connector to the remaining - on the first and on the second. Additionally you can add a balancer wire. Thats it. Regards
1. Stick 2 cells back to back (using CA) and solder the positive terminal (cell 1) with the negative terminal (cell 2) to form the center lead. You might want to use scotch tape to keep the two open terminals from contact.
2. Next, cut the JST-XH 2S Wire Extension (idProduct=9735) into two halves.
3. Solder the three leads of the Lipo battery to the male end of the JST-XH to form the charging connector.
4 Finally, solder the two extreme wires of the female half of the JST-XH 2S Wire E
I bought 110 of these batteries, all of them are weak, do not deliver more than 160mAh, and not even close to 10C. These batteries are unusable, and HC is refusing to exchange them! I'm supposed to measure capacity for 110 pcs within 30 days, that's their customer service :-( HC sells unchecked, unreliable products and does not exchange them when a massif problem occurs - finally, HC becomes very expensive in these situations! I've found another source, same price, but free shipping!
Stay away from this battery!!!
The Zippy 240mah can deliver 199mah at best. When talking weight and performance I would recommend Hyperion CX UM 160mah, it deliver 100. Please read the full review for more information. www.link
The first 100 I used delivered 240mAh without problems. The next 110 were really bad (160mAh). It's for sure a bad batch and HC doesn't recognize that.
*AvistarAddict: I've better things to do than test bad batteries that cost too much.
I found another source for a 0.99$ battery that delivers 285mAh.
You make your own tabs. There is a link somewhere to the JST connectors with bare wires. 2 cell, negative lipo battery lead is black lead on balance connector you make. First connection on the series circuit (where you connect the plus and minus terminal in a multi cell pack) is the first positive lead for your balance connector, and every time you add a cell in series the connection becomes the next positive balance connector. 2 cell : Three total leads, one negative (black) and two positive (red and other colour not black). 3 cell: Four total leads, one negative and three posite leads. These can be made up from a 24 awg wire, depending on the Ampacity of your pack. The plus minus bat leads that go to your ESC should be of a wire gauge appropriate for the load being connected.
Hobby King has them: www.link JST-XH Wire Extension (10cm)
Just cut off the male end leaving the amount of lead wire you need and solder to the li-po pack tabs using the correct polarity. Cover exposed wire and tabs with heat shrink tubing. Save the female end for future use.
They come like in the picture above, with two steel tabs. No need for special training, if you are insecure about soldering lipo cells put a small wet (moist!) towel over the lipo and ONLY the tab you're soldering currently (to prevent shortcut!). First put on a small amount of soldering tin, tin the wire too and bring together, put the iron on the wire.. Finished :o)
Remember, when soldering 2S packs or above, you'll need balance tabs too or you will get unbalanced packs with a short lifespan!
yes solder the pwer lines on to the end of the small strips(as far as possible from the lipo it self) now you can role each powerline so it becomes a nice compacked join. DO NOT FORGET TO INSULATE THE JOINES!!
Great in a 1s application on parkzone sukhoi and fixes the CofG Issues as well as giving around 10 mins flight times.
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16 thumbs up!
Bought two of them, true capacity for both of them were approx 170<. Where has the 30pcnt missing gone to? I bought 138mah version they had the same problem!!! Maybe Zippy brand isn't as reliable and trust worthy as before.
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11 thumbs up!
I bought eight of these cells and made them into 2s packs for use with the 18-11 10 gram outrunner. They provide plenty of power to run a gws 4.5x4 at about 1.8 amps. The problem is that even at this low dicharge rate (about 7.5C) all four packs consistanly hold only 150mah. That is only 62pcnt of the rated capacity. These can really only be 150-180mah cells and should not be sold as 240s. The stated 6g weight is correct.
Recently received 4 of them. The real measured capacity (after 3 cycles is only about 200mAh (1C charge/discharge) or 175mAh - 1C charge/1,5A (6C) discharge :-(. Is it normal, or a wrong series? Excetp the lower capacity, the cells are okay.
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9 thumbs up!
Can't really go wrong with these and they work great in the PKZ UM Sukhoi and P51. As noted above, the capacity is less than 240mAh, but it is clearly more than the normal PKZ/E-flite lipos and runtime is definitely increased... all for under $2.50 each (including the connectors). That's why I just bought another 10!