Hello everyone ,
I am sorry if this has come up before and I am just reposting it . I looked in the search some and did not see it ..
I have an electric bike (new to it) and am using sla batteries to get the 48 volts I need/want for a 1000 watt motor . They are heavy as you all know but not so expensive as the Ping's etc I have seen ...
I am into RC Airplanes (electric ones) so I have some experience with Lipos ..Anyhow to the question .. I have just started seeing some lipos that will work and are not too expensive it looks like ... Can someone please confirm my speculations about wether this will work
Spec.
Capacity: 5000mAh
Voltage: 6S1P / 6 Cell / 22.2v
Discharge: 20C Constant / 30C Burst
Weight: 754g (including wire, plug & shrink wrap)
Dimensions: 145x52x50mm
Balance Plug: JST-XH
Discharge Plug: 4mm Bullet-Connector
That's the specs from the website .. I am thinking of using 2 batterys for 44.4 volts then 2 more to get the Amp Hours up to 10 . So with 4 of these batteries I can end up with a 44.4 volt 10 Amp hour battery that weighs only 6.7 pounds and comes in at about $200 ..
Please , Please .. can someone check my work or numbers to see if I am right and does anyone else know a way to get a comparison battery for less or the same $$$ ..Thanks sooo much in advance for any help I can get with this ... Don J.
Been there, done that lol!
Those batts are great, ur bike will go super.
Just be careful not to smoke those batts. For the record mine lasted about 2days before I acidentally shorted one... then Wooooosh, Bang!
Hello Colin , Thanks for the reply .. I have "done that" too but with smaller RC Plane batterys .. They sure can get damaged fast .. AND scared the heck out of me too .. I can't imagine how I'd feel if I did that to a Bigger ... More Expesive...Battery Sooo what if I was to use more of the ...2000Mah batterys that would still work and if by some chance I short out one it's not as expensive,,,
Thanks for confirming that this will work I do appreciate it very much .. Sorta suprised that more people don't talk about it or do this for lower price good lipobatterys ... Well thanks again .. Don J.
I definately wouldnt bother with smaller ones (If I was prepared to have lots in parrallel I would use 2300mah A123 LifePO4s because they are risk free. U can get them on ebay from singapore at about $5 each - very high 30C discharge)
I think the good thing about those lipo packs is that they are 5000mah. then you only need 4 to do ur 2s2p 48v 10ahr pack. It will work fine if u mount the batts in a box away from any body parts lol!
Nice to see some one re-invented the "wheel" again! My Chiropractor Friend made me a battery box case for my Tenergy blue race car pack and use it on my bike and I installed an ammeter and was surprised how much current it can develop. Some cell blew up also and used the bad battery pack to make bicycle head light replacement instead of old Gel Cell and new charger since it has different charging.
KB1UKU
Hello , I looked into these A123 batterys and at first was excited about it .. But when I figured out how many of these cells it would take to build a battery ... 60 cells to get a 9.2 amp hour and 49 volts .. which is at the best price of $8.75 each when buying 16 at a time comes to $525.00 so suddenly I'm not so excited about this so much now ...If anyone has any good resource for these A123 cells please let me know ...
I still would like to try the lipo route the 5000 mah batterys at 22 volts can be had for around $50 each 4 of these would build a nice battery I think ..
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Thanks sooo much to everyone who helped and everyone who read my jibberish , Don J.
You propose using only 12 cells in series, which results in LESS VOLTAGE than the stock battery, and is likely to cause premature shut off of your controller. Using 14 cells in series will allow much better performance and charge utilization, as the voltage of a 14 cell pack at end of discharge will be about 42 volts, which is much closer to the lead-acid batterys discharged voltage. Specialized charging will be required, do NOT attempt to use the lead-acid charger!--Bob
Robert M. Curry
Thanks for the reply Bob ,,, The controler I am using this with can use 24 , 36 , or 48 volts .. It only changes the output of the motor . So thanks for your concern but it won't matter if there is a few volts less except the bike having slightly lower top end speed which is no big deal seeing as the top speed is faster than I'd want to go .Thanks again , Don J.
Although the added top speed may not be important in your case, the added RANGE/DISTANCE will make quite a difference, because your controller, if set for 48 volts, will shut OFF your bike when your battery drops to around 42 volts, which will happen way BEFORE it can be fully used, as your 12 cell series would be usable down to 36 volts otherwise. (This is a function of the controllers "Low battery cutoff") Do not set the controller for a 36 volt battery, as then the cutoff would be (about 30 volts) below the safe discharge point for your 12 cell series pack, (36 volts) leading to battery destruction from excessive discharge! Unless you can set the low battery cutoff to 36 volts, with the controller in "48 volt mode" you need more cells!-Bob
Robert M. Curry