range on a cyclone with lipo....

[gerlewis]

hi guys, at a guess how many miles would a 6-Cells 22.2v 30C 2800mAh Li-Po Battery take me on my 500w cyclone?
also a similar guess with a 5000mah?

my guess is 2800mah - 3miles
and 5000mah - 6miles. what do you reckon?

Thanks
Ger

 

[Kaño]

In my experience with the cyclone 500W if you keep it revving high:

2800 3 miles
5000 5.5 miles.

Remember that it is wise to use your lipo to max 80% DOD. (Range was calculated accordingly)

 

[gerlewis]

thanks, im new to this, as I currently use lifepo4, but am tempeted to sell it and use 2 5000mah sticks (one for the morning commute and one for afternoon).

a couple of quick Qs if you have the time.

1. will the fact its 22.2v (not 24v) make the bike slower - infact is the lipo slower/quicker than lifepo4.

2. do I just need to buy a charger and im away? or do i need bms etc?

The attraction to lipo for me now is that the packs are much smaller than my hefty lifepo4 thanks to the high C rating.

Ger

 

[Kaño]

1. Voltage is what determines the speed, so it will be just a bit slower, but since Lipos could deliver a lot of current (C rate) you will get better acceleration. (22.2V is nominal; the pack would stay at 24V or so for a while)
2. Yes you need to buy a LIPO charger; I have an RC charger/balancer IMAX8 that is working fine. You don`t need a BMS, but you will need a CA, or Watts up, or some stuff to monitor the pack voltage, you must never go under 3V.

Lipos are great, very small for the power you get!

There is a very useful treat to read about lipos in the forum, give it a try, it is very important to know how to handle them if not it could be dangerous: http://endless-sphere.com/forums/viewtopic.php?f=14&t=9170

 

[gerlewis]

Thanks for the reply. Good information, yes I have had a look at that thread and will have a proper read when I get more time.

One question has arisen already!
I I was to run 2 x 11.1v packs instead of 1 22.2v pack, would chain-linking them provide me with enough capability to output enough wattage? or does chain linking just increase the ah?

ie if each pack is 2200mah and 15C (3s) would it a) put out 300watts for twice the time, or b) put out 600watts for the same time as 1 pack would put out 300watts

Hope that makes sense?!

 

[MrBoots]

Gerlewis, by "chain-linking", I'm assuming you mean running the batteries in series? If so, then yes, you're voltage would be doubled to 22.2v while the ah remains unchanged at 2200mah. If you ran them parallel, the reverse would be true - 11.1v @ 4400mah. Hope that helps!

 

[gerlewis]

Thanks!

how do you physically connect them to make the difference?

 

[MrBoots]

Here's a link that explains it far better, more in-depth than I could = http://www.zbattery.com/Connecting-Batteries-in-Series-or-Parallel. Good luck!

 

[gerlewis]

Thanks!

Is it possible to connect a 18.5v to a 7.4v in series? to produce 25.9v?

also, how would one charge these two if they were joined together? - assuming you would have to disconnect them, can these ebay lipo chargers charge 2 sticks at once?

Ger

 

[MrBoots]

Yep, it's possible in series but ONLY if the capacities and current (or C) ratings are the same. I'm actually considering of running the exact same set-up since 7.4v lipo's are just dirt cheap these days. Just be mindful that they can only be run in series and not parallel.

As for charging, I've honestly never charged batteries with different voltage values together and even with a balance charger that could facilitate that, wouldn't do it. But I'll defer to one of the lipo experts here so they can chime in.

 

[gerlewis]

Thanks, my other idea is 14.8 x 2 to get 29.5v (see my cyclone thread)

My lack of knowledge comes now at the charging end of things! I presume I would have to charge them 1 at a time, or get 2 chargers.
Also I would have the fiddly aspect of having to un-link them before charging every time.

Ger