Conhismotor 48v 10ah LiFePo4 (LiMn2O4) in aluminium case

[shorza]

I wonder if these are the cells: http://www.zjzhenlong.com/en/html/en-2.html
The cells, packs and chargers look the same, but i guess there's a million Chinese companies making these.

 

[jbond]

it is hard to find reliable information on Li(NiCoMn)O2. This site does a bit of comparing: http://www.xcgdbattery.com/cp_look1.php?typeid=1&id1=65. Googling Li(NiCoMn)O2 just seems to bring up Alibaba sites.

Thats really instructive. Look at 36v10Ahr and compare like for like.

LiMn2O4
Cell: 2.7v -> 4.25v
Charging voltage: 42v
Weight: 3.7Kg
Life: 600 cycles
Cell layout: 10s (?)
Typical battery usage, 42v fully charged. Typical controller cut off 31.5v

LiNiCoMn
Cell: 2.7v -> 4.25v
Charging voltage: 42.0v
Weight: 3.3Kg
Life: 800 cycles
Cell layout: 10s (?)

LiFePo4
Cell: 2.0v -> 3.8v
Charging voltage: 43.8v
Weight: 3.9Kg
Life: 2000 cycles
Cell layout: 12s (?)
Typical battery usage, 43.8v fully charged. Typical controller cut off 36.0v

This fits with what we see in the market. Very early on LiCo was thrown out as being too dangerous. Most commercial packaged batteries were LiMn. Cells were plastic covered rectangles. Adding some Ni,Co to LiMn and switching to pouch meant more cycles, less weight but the same electrical characteristics. LiFePo was an extended lifetime option on expensive batteries but the different electrical character meant 12s instead of 10s. That meant that typical voltage range changed to 43.5->36 from 42v->31.5v and weight/volume increased a bit.

So I think we have two predominant setups on sale now. Cheap LiNiCoMn tuned for a sweet spot of lifetime vs weight vs total materials. And an expensive option of LiFePo tuned for lifetime with roughly the same voltages.

I think cheap non-programmable controllers, LED battery capacity indicators and so on, are all set to a voltage range of 31.5v to 42v. This protects the battery from deep discharge. It works with all the LiMn and LiNiCoMn batteries used on cheap e-bikes. If you fit a genuine Ping style LiFePo battery, you get a slightly higher voltage in normal use, but now you're relying on the battery LVC instead of the controller LVC which means a deeper discharge. This may mean a shorter lifetime on the battery than specced. The LED capacity display will be wrong. And the overall weight/volume will go up slightly.

So my guess is that your Conhismotor battery is whatever LiNiCoMn mix is currently being supplied by the cell manufacturer and not LiFePo.

 

[Pedalex]

i also have a Conhis pack - 48V 10 Ah in the aluminium case. no idea what cells they really use. hasn´t done more than 4 or 5 full charges maybe 60km but one of the cells is down to 2,09 V so the BNMS cuts off immediately - all others are at 4,1.

i asked Jason to send me a spare cell. that was 2 weeks before chirstmas - not here yet but last week he gave me atracking number. dispatched on 28th Jan....

 

[dnmun]

what is the voltage on each of the cells when you are charging. can you record and list them so we can try to help you? did you file a grievance already?

 

[blueb0ttle2]

This thread got me curious about Conhis motor battery packs as a relatively cheap alternative. Are they any good? The stuff looks identical to golden motors, which doesn't appear to have a good reputation.
Edit: Upon further reading, Conhis motor doesn't seem to have that good a reputation either. How sad.
I'll probably use ping then.

 

[Hyena]

Where's the mystery?? it clearly says lithium polymer on the label.

LIthium POlymer = lipo

edit: Never mind, I didn't realise this was an older post and there's been a few pages of replies since!

 

[shorza]

It says "lithium power", unless you see something that I can't.

Pedalex, is it possible for you to measure a cell while charging? Your battery pack does seem a little different to my 48v pack. I don't think mine would be able to split in half like that. How do you know that it's only one cell that is the problem? These packs are 3 parallel, so aren't you measuring 3 cells? Do the cells have any writing (numbers) on the sides?

Bluebottle, the pack is doing all right by me. Although I charge after every use, and only use about 3ah. Not too sure how many ah it actually has. The fast charger has problems with my pack, but Conhis is sending me another apparently. They said the fast charger was for LiFePo4 and that the pack is actually LiMn2O4. My slow charger seems to work ok.

jbond, the packs/cells are definitely NOT LiFePo4, Conhis has stated that to me in an email. Even though they are still selling them as LiFePo4 http://www.conhismotor.com/ProductShow.asp?id=43

I'm happy with the pack so far. It slots into my bike fine, and I feel it's safe by being locked.
I have set my CA to limit the current draw to 15amps which i'm sure is doing the pack damage. But time will tell.

 

[Hyena]

It says "lithium power", unless you see something that I can't.

I need my glasses, and a coffee...
Given most chinese labels I've seen on things they probably meant it to say polymer not power :lol:

 

[Magneto]

I'm curious too Pedalex about if you have one cell bad or a whole bank. How many cells were in the banks? shorza had 3 cells per bank times 13 (3P 13S) for 48V so 39 cells all up, not sure what I have in my 36V pack.

If the whole bank is measuring bad, then maybe one bad cell is bringing them all down to it's voltage? Maybe the problem was actuall a bank parallel wiring failure rather than a dead cell?

As far as I know, to measure individual cell voltages, you have to disconnect either positive or negative from the paralleled bank.

 

[Magneto]

shorza wrote:


'I wonder if these are the cells: http://www.zjzhenlong.com/en/html/en-2.html
The cells, packs and chargers look the same, but i guess there's a million Chinese companies making these.'

They do look like the right shape when comparing to the ones you have found in your pack shorza,

very brief look but no mention of chemistry, did you find anything on that page speccing what the cathode chemicals are?

 

[Pedalex]

it´s a 13s pack. i measured each cell and all except the bad one had 4,1V
that´s what it looked like:

 

[shorza]

It's a 13s pack, but how many cells are in each of those 13? Mine had 3. Yours does look slightly different to mine, apart from the different color shrink wrap, out looks like your bms isn't wrapped up with the cells like mine is. How much did the extra cell cost you?

 

[Pedalex]

oh!

i didn´t know there are more cells - i thought it´s 13 single cells
so i asked Jason to send me just 1 spare cell. did´nt have to pay fot it and Jason sent it with the tumb throttle i ordered.

tracking number shows that it´s already here in Austria so i guess it´ll be here within the next two days and i´ll try to fix my pack this weekend.

 

[dnmun]

why did you say the cell was bad? there should be 13 cells of the LiMnO4 to make the 48V, and the 4.1V should be the normal fully charged voltage. doesn't seem like that is a problem imo.

 

[Magneto]

From the look of your original photo Pedalex, it might be two cells per bank, but cant be sure, can you see if there are two 'pouches' stuck together?

Hope all goes well with your repair when the cells actually do arrive. I would be surprised if you actually get the right cell/cells delivered, as it looks like they are using a combination of batteries in the aluminium case...

Shorza's and mine have a 'Tehao Power' label on the side of the case, is this your brand as well?

My battery is going fine touch wood, after about 15 charges, I do like the locking ignition switch which locks the battery in the bike with the aluminium mounting rail that is supplied with these batteries. I also like the light weight, less than 3kg all up for 12Ah 36v.

 

[shorza]

Pedalex, did you receive the extra cell yet?

 

[Magneto]

Also keen to hear how you go pedelex

Shorza, what happened to you r last post? disappeared for some reason.

Have got my 11T to 34T DNP Epoch 7 speed freewheel installed now complete with new 7 speed shimano tourney shifter, it rocks. My best with my old freewheel was 13T, at gear position 5 that feels like midrange now. So happy with this upgrade, I can spin easily to 60km/h with my 53T chainwheel on the crank. Cruising at 30km/s is like childsplay, putting down a bit of extra pedal power is more efficient as not spinning so fast, I highly recommend one of these.

Installation for me was easy, no spacer required with my bafang on the cluster screw in side, and simply swapped an existing spacer from one side of the dropouts to the other to account for the extra gear, slotted straight in. Wired up the new shifter and bob's your uncle.

The only problem was the DNP Epoch freewheel came pretty well injected full of grease from the factory, which made it pretty stiff, thought the bearings were too tight from the factory but after running in it's spinning fine now. Squirted a bit of INOX in the bearings to speed up this process. Was silent with all that grease in there, but now after about 40km is ticking like a shimano freewheel, albeit pretty quietly.

Had got worried as had read on the net elsewhere that the DNP epoch can have quality control issues with one being overtight bearings, but I think it's just the way they grease them up. Seems to be pretty solid, they are made in Taiwan, but are reportedly OEM on cheaper bikes in the market. Regardless, has nickel plate, easy shifting aids being shifting ramps and angled teeth as well as shimano index spacing, changes perfectly with my shimano shifter.

 

[Pedalex]

@Magneto
also have 11T and 53T - amazing difference but i couldn´t make a vmax test with the 53T since it´s still winter here and there´s too much gravel on the roads

with 48 -11 my max speed with the 1000w 48v Conhis DD was 57 km/h - now i´m waiting for the 1000w Puma i ordered two weeks ago.

Pedalex, did you receive the extra cell yet?

:| :| :|

not really.
that´s my pack

and here is what Jason sent me WTF ?

i already sent him a mail with these pics - hope he can find the right cells and send it together with my next order.

 

[jbond]

Have got my 11T to 34T DNP Epoch 7 speed freewheel installed now complete with new 7 speed shimano tourney shifter, it rocks. My best with my old freewheel was 13T, at gear position 5 that feels like midrange now. So happy with this upgrade, I can spin easily to 60km/h with my 53T chainwheel on the crank. Cruising at 30km/s is like childsplay, putting down a bit of extra pedal power is more efficient as not spinning so fast, I highly recommend one of these.

I've seen dire warnings elsewhere to avoid DNP due to quality issues. Mainly that the gear material is just not up to it and the ratchet/bearings break up. Be very interested to hear how it holds up. 26", 48t + 11t-30t 7 speed makes a lot of sense to me.

 

[Magneto]

As I suspected pedalex, the chances of him sending the right cell were pretty remote. That cell is identical in every way to my last battery that came with my 'greenewheels' bike, it's not lipo construction (not a pouch) has a metal box to keep the cathode in, and is quite heavy compared to the lipo. It's a limn204 as far as I know. Not a good idea to wire that in to the pack, and it does sort of look like you were right about your cells, it does look like a 13s with 13 cells only looking at that new photo. I would measure the cells accurately as well as describe them in detail plus detailed photos.

Jbond, hope it lasts a while, better keep the chain clean by the sound of it. Maybe I can replace the 11t when it wears out (usually the first to go) it can be removed.

Trouble is, this is the only freewheel in the world that has cogs smaller than 13t. Shimano should fire up their machine and start making them again, the e-bike market is enormous, (22mil ebikes made in china 2010)

Anyway, for now the freewheel is awesome, will look after it, including oiling the bearings and hope shaman makes one before this one wears out, or I'm back to 13t and spin city

 

[shorza]

Shorza, what happened to you r last post? disappeared for some reason.

I deleted my last post as I was referring to another post that got deleted by the poster.

Pedalex, that is just a frocking joke. Conhismotor should really get their act together. Send them an email with you pictures and explain that you are on the endless-sphere.com forum and would hate to write a bad review about their company. From the looks of it, Conhis asked their supplier to send an extra cell without stating the specifics. NOT good enough.

 

[Pedalex]

took 4 months but my pack is ready to go again.

Jason sent me two "lookabitliketheothercellsbutsmallerinsizeandhopefullynottoomuchdifferent"-cells :wink:
yes, the two cells - front of the left pack - they are a bit shorter and i have a bad feeling about leaving them at the charger when i´m not around

by the way - i really hat soldering

 

[shorza]

Only 2? Aren't they 3 paralleled?

Yeah Jason finally shipped me out another charger, one that was 'meant' for my battery. The problem being that even when the battery is super low, it wont trigger the charger to start.
On the charger's voltage it shows about 25 volts.... gee thanks.

 

[Pedalex]

13s2p

 

[shorza]

Strange, mine's 13s 3p - 48v 10ah apparently.

Finger's crossed you have the same chemisty's.