Best Battery?

[Doctorbass]

Get into the 25ah 48v + arena and it's a whole different story tho..

Soon :wink: my 360 10C konion cells should give me 27Ah at 84V.. and 35 lbs to share and fix on the bike.. :lol:

And running to 64kph for an hour and half...

Doc

 

[Jay64]

If you're really going for speed, you could use a big pack of a123s because they have the fastest discharge rate. Then you could add a big block of super-capacitors that can release enormous amounts of energy instantly. Use the a123s to get to 100mph, then connect the capacitors to the motor.

Film it. You could be on the evening news.

I get the feeling from this post that this would result in something bad. Remember, I am a newbie to EV, if something is seriously going to blow up between my legs, please don't tell me to do it.

 

[Beagle123]

I don't think it would blow-up, but I think it would be dangerous. I'm scared at 30mph.

Hey Doc, I can't wait to see your new set-up. Please post pics and details. When are you going to get them?

 

[Jay64]

I don't think it would blow-up, but I think it would be dangerous. I'm scared at 30mph.

I guess dangerous is a relative term. Dangerous in what way, because of the speed that can be obtained, or dangerous in that something bad will happen to the bike?

 

[Doctorbass]

I don't think it would blow-up, but I think it would be dangerous. I'm scared at 30mph.

Hey Doc, I can't wait to see your new set-up. Please post pics and details. When are you going to get them?

I already have them :wink:

What is VERY LONG is to measure each cells capacity, internal resistor and Wh !!!
(I use me RC charger (the famous megapower 960SR 12s) )

It took around 1h to cahrge eact cells and 40min to discharge/test each one!!!


:lol: FREE CELLS BUT..... i dont want to calculate my work hour rate$..... to measure each cells

I choosed to do this to perfectly match these cells in the 20s 18p configuration to have each 18p group equal on Wh/capacity/internal resistor... to have no problem about their self balancing...

The miracle is that these are rated 10C around 120Wh/kg and they do not need balancing !!!.. imagine a 20s pack WITHOUT need of balancer!!
Sweet!

No more need to worry about balancer/individula charger..etc only the lvc protection.

I plan to finish to measure these cells in january and i plan to built the pack for february.

I can charge each cells at 3 or 4A so a 18P would mean a charger of 60A

60A at 84V need a 220 outlet :lol: 22A on a 220V outlet...

maybe i will charge them with 120V (1500W) instead of the 5000W of the 220......

That should take 40-45min to fully charge them with a 120V acces..

 

[Beagle123]

18p, 20s ?!?!? Wow. I can't wait to see what it looks like. The charging sounds awesome too. I may try charging my bike at 200 amps with this:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=300148554794&ssPageName=STRK:MEWA:IT&ih=020

I have a 200v outlet in my living room. However, I'm using emolis. The manufacturer say the max charge rate is about 1.2C. I've heard that a123s reccomended charge rate is 3.3C or so. I find it a little hard to beleive, but I hope so.

 

[GGoodrum]

a123-M1 cells can be safely charged at rates much higher than 3.3C. The a123Systems site recommends 10A, which is at a 4.4C rate, but they also say that because of the proprietary nantechnology manufacturing process used, the cells can actually be charged in as little as 5 minutes, with a big enough charger. That would be a 12C rate. In the RC world, many have regularly charged these at 20A (8.7C...) and some have tried them at 30A rates, with no apparent issues. Personally, I used ot charge my packs at 20A all the time. I still have some 10-cell packs with hundreds of charges on them and they are still going strong. These are used in RC electric helicopters that can hit regular peaks of 90-100A, so they are getting a lot more abuse than we are doing to them in bikes.

Somewhere here is a link to the Killacycle drag bike. This beast does the 1/4 mile in about 7-1/2 seconds at a speed I think was up around 135-140 mph. The video will make you wet yourself. It is using one big honkin' pack made from 110 cells in series and 11 in parallel. I think what you need to play with the 600cc boys will be something in between that, and our highest performing ebike setups here. 8)

Should be fun.

-- Gary

 

[Doctorbass]

18p, 20s ?!?!? Wow. I can't wait to see what it looks like. The charging sounds awesome too. I may try charging my bike at 200 amps with this:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=300148554794&ssPageName=STRK:MEWA:IT&ih=020

I have a 200v outlet in my living room. However, I'm using emolis. The manufacturer say the max charge rate is about 1.2C. I've heard that a123s reccomended charge rate is 3.3C or so. I find it a little hard to beleive, but I hope so.

Here is some pics of the current status of developpment of my next battery pack:

 

[monster]

I've got a heavy steel bike with SLAs. With a disc front brake the stopping distance isn't any problem.

you must be kidding! if the road is wet your screwed!

i have a front disc but i have to be careful when i use it because it locks the front wheel and you loose control. rear discs is what you want when you have all your weight distribution on the back. i have electro mag brakes cos i can't fit rear discs.

 

[Ypedal]

I use my front disk brake all the time, wet or dry, it's all relative to the force you apply to the lever, disk brakes are very modular, pull a little.. stop a little.. pull hard.. stop hard !

Good rubber makes a difference here ! * ( edit : Good.. not god ! lol )

 

[Jozzer]

God rubber? Sounds like it might work :lol: