LiMnCO2 Batteries are they worth it?

[Krazy]

Hey all I am new to the e-bike world and would like to get some opinions on these lithium manganese dioxide batteries.
Im currently in the process of building a very high powered e-bike and want the best I can find (within reason), I have read on a website or 2 that these offer more cycles, more power for less size... Is this true? As I am new to this world I dont wish to just take one or 2 websites views as gospel as there obviously financialy involved. If anyone could help me on the subject that would be grately appreciated, as in Australia I am really struggling to find anyone with knowledge of these batties or any batteries to suit my needs for that matter.
Also if there not all cracked up to what there supposed to be, whats my best alternative?

Rob

 

[ian.mich]

Hey all I am new to the e-bike world and would like to get some opinions on these lithium manganese dioxide batteries.
Im currently in the process of building a very high powered e-bike and want the best I can find (within reason), I have read on a website or 2 that these offer more cycles, more power for less size... Is this true? As I am new to this world I dont wish to just take one or 2 websites views as gospel as there obviously financialy involved. If anyone could help me on the subject that would be grately appreciated, as in Australia I am really struggling to find anyone with knowledge of these batties or any batteries to suit my needs for that matter.
Also if there not all cracked up to what there supposed to be, whats my best alternative?

Rob

They will be the best ebike battery in the coming years. right now, We have not found a very good supplier other than bare cells from EIG, which are very pricey. The step below NMC and soon-to-be last-gen battery is RC LiPo, which takes care and research to assemble, and is still a bit of a pain. NMC is the same weight as LiPo but has similar safety as LiFePO4, so it is a step in the right direction. i believe it also has a few more Wh/kg than LiPo, but is not capable of the 20C or as much as 130C that turnigy and turnigy nano-tech are capable of.

 

[Krazy]

I found these??

http://www.electricrider.com/batteries/index.htm#HighCurrent

 

[ian.mich]

I found these??

http://www.electricrider.com/batteries/index.htm#HighCurrent

expensive.

 

[Krazy]

What about these then, seem well priced

http://www.bmsbattery.com/48v/249-48v-10ah-lithium-ion-electric-bicycle-battery-pack.html

48V20Ah Li-Ion Shrink Tube EBike...
48V20Ah Li-Ion NiCoMn shrink tube electric bicycle battery pack. Included 13s polymer cells, 1pcs 15A continuous discharge current smart BMS, 1pcs 48V4mps EMC-240 Lithium Ion battery Alloy shell charger.
$369.00

Am I right in sayin 2 off these in parrarel will give me 40ah, 3 60ah and so on?

 

[bowlofsalad]

"very high powered e-bike"
Vague as hell. That could mean anything. Care to elaborate?

Are you very familiar with a123?

 

[ian.mich]

What about these then, seem well priced

http://www.bmsbattery.com/48v/249-48v-10ah-lithium-ion-electric-bicycle-battery-pack.html

48V20Ah Li-Ion Shrink Tube EBike...
48V20Ah Li-Ion NiCoMn shrink tube electric bicycle battery pack. Included 13s polymer cells, 1pcs 15A continuous discharge current smart BMS, 1pcs 48V4mps EMC-240 Lithium Ion battery Alloy shell charger.
$369.00

Am I right in sayin 2 off these in parrarel will give me 40ah, 3 60ah and so on?

discharge rate is 0.75C, base level RC lipo is 20C. Plus, BMSbattery is absolutely terrible

 

[Krazy]

"The system will require a battery that can put out 400 amps for 3 second bursts and will never exceed 50 volts" Paraphrasing.
Its 20000w at peak and am looking at getting 40-60ah is this possible? how high a "C" should I go?

 

[spinningmagnets]

If you are serious, and not joking...you need LiPo, regardless of the hassles of charging and maintaining a LiPo pack. You will not get that kind of current from a LiMnCo2 pack.

...48V20Ah...Am I right in saying two of these in parallel will give me 40-Ah, three will give me 60-Ah and so on?...

Yes, that is correct.

 

[ian.mich]

"The system will require a battery that can put out 400 amps for 3 second bursts and will never exceed 50 volts" Paraphrasing.
Its 20000w at peak and am looking at getting 40-60ah is this possible? how high a "C" should I go?

Jesus. for 50Ah at 400A that would take 400/50=8C. Hobbyking lipo should be run at 25% its C-rate so you need at least 32C, lots of people like 40C lipo. Since you have a very high power bike you should contact jonescg and he will build a bulletproof 40C pack from bare cells, and for 50V, 12S is perfect.

 

[Krazy]

Yeah I am serious, so what li-po can give me that 60ah that I wish to get?

So the higher the "C" the better? like I see these Turnigy Nano Tech at 130C are they the go?

When batteries are alligned in series do the ah increase or stay the same?

 

[Krazy]

"Since you have a very high power bike you should contact jonescg and he will build a bulletproof 40C pack from bare cells, and for 50V, 12S is perfect."

Whats the 12s? please excuse my ignorance.
And how big would one of them be at 60ah?

 

[ian.mich]

"Since you have a very high power bike you should contact jonescg and he will build a bulletproof 40C pack from bare cells, and for 50V, 12S is perfect."

Whats the 12s? please excuse my ignorance.
And how big would one of them be at 60ah?

12S is 12 cells in series. Contact jonescg for details.

 

[Krazy]

Cool thanks alot for your help, been struggling to work it out on my own reading forums etc.
Greatly appreciated.

Rob

 

[spinningmagnets]

Connecting cells in series raises the volts, parallel raises the amp-hours of the pack.

If you have enough budget, Nano-Tech is what the racers use.

12S is common, its performance is usually calculated at about 44V for designing a system. If you charge to 4.10V per cell, and discharge to 3.65V, a 12S pack would run between 49.2V when charged up, and 43.8V when the controller finally cuts it off.

 

[Krazy]

Yeah so if I was will to spend that much to get 60ah on nano techs I would need 12 sets of these (24 total).

http://hobbyking.com/hobbyking/store/__19156__Turnigy_nano_tech_5000mah_6S_65_130C_Lipo_Pack.html

Or these $30 bucks cheaper

http://hobbyking.com/hobbyking/store/__17256__Turnigy_nano_tech_5000mah_6S_35_70C_Lipo_Pack.html

I'd have to get a hell of alot of distance outta that, but alot of money.

So can you charge them as a bank or would it be 24 individual charges?

 

[jonescg]

Hey, yeah as mentioned I can do LiPo packs. I can do up to 25 Ah of 40C LiPo. For any capacity larger than this, I'd really recommend EIG or A123 packs, since they are about the only viable option for these discharge rates and capacities. The EIG won't be cheap, but they are an impressive cell.

You do realise that a 14s5p pack of LiPo will weigh just under 10 kg, which is about as heavy as you would ever want it for an e-bike. If you were building a short-range motocross bike with adequate suspension you can push it to about 30 kg, but I wouldn't go putting this much on a bicycle.

 

[leffex]

I'd have to get a hell of alot of distance outta that, but alot of money.

So can you charge them as a bank or would it be 24 individual charges?

Licomn 48v10ah gives me 20a, sag voltage is 6v, weight 5kg, Warm battery
(goes OK with 30a but very warm battery after 10km)
(goes but not sustainable 45a, only tested for a ride or two)

I have some lipos i will start using soon. Only need to mend my wires and the snow and ice have to melt and i will go try em out.

20kw max motor.... Feels that u need a special battery assembled because then you might get a special charging system for it without needing to tinker up your own?

 

[dnmun]

if you go with the lipo, and this large, do not try learning to charge them inside an apartment building or other rented structure. do it only inside your own home. if you kill someone in a fire you may be held liable for manslaughter by negligence.