Elecscoot E4 scooter with LiFePO4 cells

An area for all you bikers who now run your two wheeler on battery power, scooter owners to.
cjstephen
Posts: 4
Joined: Wed Aug 06, 2014 8:55 am

Elecscoot E4 scooter with LiFePO4 cells

Postby cjstephen » Sat Aug 09, 2014 11:49 pm

Hello All!

I wondered if any of you had any advice on finding a new home for a barely used, road registered, theoretically 60mph electric scooter?
The catch is that it has never exceeded about 20mph and I believe was supplied with the wrong charger (labelled LiIon) which
has in any case since blown!

I asked Elecscoot to fix it naturally, but over a year and a court order later they've quit their premises and even if I pursued them further
I can't see them having any assets on their books. Annoying as Ian Allison still seems to be selling suspiciously similar bikes on Ebay.

The scooter cost £4k and has quite a few barely used LiFePO4 cells, whose health I can't determine, so I'm loath to send it to a general scrap firm
without some attempt to find a better home. The cells have had very few cycles, although if my suspicion of the charger is well founded the wrong
current and voltage control was applied through these cycles. The battery may also use super-capacitors. I held off on invasive investigation whilst
there was a hope of returning it.

Now I could spend months taking the bike apart myself, researching the charging characteristics of the cells and designing power electronics to
check the cells and supply the correct pattern of constant current/voltage at each stage fixing the problems but realistically I don't have the time.
I don't have the appetite to spend the required time and money setting up an electric vehicle workshop.

However, it's entirely possible that if the cells aren't damaged they could be reused/refurbished by a firm/person with the appropriate knowledge
and kit. In fact if the cells/chargings problem were fixed the scooter should be properly roadworthy. It's possible only the correct charger is missing.

Do any of you know of any businesses/people who might be interested in taking second hand electric vehicles or cells, particularly with LiFePO4 cells?
How would you sell on / dispose of a faulty electric vehicle?

Many thanks,

Colin

ChrisBarron
Posts: 244
Joined: Tue Dec 11, 2007 11:26 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby ChrisBarron » Sun Aug 10, 2014 6:38 pm

Hello Colin, I take it that you have the Elecscoot 4 if you expect a top speed of 60mph and a 100 mile range ?
http://www.greenelectricbikes.co.uk/ele ... -range.htm

I don't know where they fit all the cells to get that level of performance, but there you go.

How much money would you like to get for it ? I might be interested, but I'm not a rich man, alternatively I would be more than happy to try help you try to get the most out of it if you wanted to try

Chris

cjstephen
Posts: 4
Joined: Wed Aug 06, 2014 8:55 am

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby cjstephen » Mon Aug 11, 2014 2:24 pm

Hi Chris,

That's the one. I scraped the website before Elecscoot disappeared so here's a copy of the E4 page: http://cjs.eudimonia.org.uk/www.elecsco ... =%206.html
It's cost me £4200 + hundreds chasing Elecscoot but at this stage if I could recoup a few hundred and know it was being tinkered with rather than scrapped I would feel less bad. Unfortunately I don't have the space or time to work on it myself, I'll be starting a PhD in applied quantum mechanics in a couple of months *gulp*. The E4 may require anything from just an appropriate charger to a redesigned BMS or checks to the cells. It still has some charge for manoeuvring atm, but at least a fuse if not some caps have gone in the 15A-72V charger and its never hit full power or capacity. At worst it's a brand new scooter frame with a 4kW motor, a bundle of high capacity cells (by my crude estimation about 30Ah @ 72V) and possibly some super capacitors. .

I found your new member posting, your work on reusing banks of LiIon cells looks impressive! I think you're better equipped than I am to track down the fault with the E4 & the LiFePO4 cells would be a new technology to investigate. I notice from your introduction you're in West Lothian. I'm near Birmingham, but when the bike's gone I need to empty a storage unit up in Elgin so in theory I could detour to deliver it to you on the way North if you were interested? Would £400 be reasonable? I see imported battery packs a fraction of this capacity alone selling on Ebay for more so even if a couple of cells are faulty should be a bargain.

Here are a few photos:

Image
Image
Image

Grumpy-b
Posts: 985
Joined: Sat Dec 01, 2007 12:06 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby Grumpy-b » Tue Aug 12, 2014 7:38 am

Just looking at the photo, that is a thundersky cell peeping out of the top. The large yellow thing. If thats so then I fail to see how you could have 20+ of those on board. There doesnt look like the space for them. That would account as to why you never got more than 20mph out of it.

Grumpy-b

ChrisBarron
Posts: 244
Joined: Tue Dec 11, 2007 11:26 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby ChrisBarron » Tue Aug 12, 2014 8:08 am

According to the website Grumpy it has 20 cells, 60V at 70Ah. (4.2kWh)
Not sure that TS or Winston ever made a 70Ah cell, so maybe they were between iterations when they wrote the tech spec.

They quoted 100 mile range, which would have to be at an average consumption of 42Wh/mile, not even bicycles get that performance and although they state they have regen which adds about 20% range, it looks like fairly optimistic literature.

In theory it should be able to manage 60mph (on a great day)

Chris

cjstephen
Posts: 4
Joined: Wed Aug 06, 2014 8:55 am

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby cjstephen » Tue Aug 12, 2014 3:24 pm

I've taken off the seat & some of the bodywork to get at the battery and I can see 20 cells, 3x6 in a tray along the bottom of the scooter and two on top.
Difficult to get to the lower tray to unbolt the connectors and assess individual cells, I'll see if I can figure out a reasonable route in.
I'll get some better lighting in about first and post some pictures shortly.

Colin

cjstephen
Posts: 4
Joined: Wed Aug 06, 2014 8:55 am

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby cjstephen » Tue Aug 12, 2014 7:13 pm

The product number on the cells is: TS-LFP60AHA
which Google tells me refers to a Thunder Sky/Winston 3.2V 60Ah LiFeYPO4 cell

I've attached a few photos of the cells in situ below.

All the cells have very low voltages after months of discharging I'm trying to manually
slow charge an individual cell that read 0.0V with a CC/CV supply limited to 3.3V & 300mA.
So far seems to be taking charging.

I wasn't overly impressed to find a stray nut lying of the batteries and a few unconnected wires
dangling out of the BMS.

Image
Image
Image
Image
Image

Grumpy-b
Posts: 985
Joined: Sat Dec 01, 2007 12:06 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby Grumpy-b » Wed Aug 13, 2014 8:12 am

Take that one out of the pack, it will be bloated andwill be putting pressure on the cell beside it. Flip the coloured red and blue sticker offthe lid between the terminals, choose the correct hex key and gently undo the lid, hopefully it will give a god awful shriek and release the pressure, if it doesnt, take off the lid, tke out the spring and holding one hand over the top gently prise he metal seal off its seat. A gentle nudge is all thats required.. Re assemble, but dont screw it down hard, take it down then back off a turn. Stick the lable on the right way, red to positive.
You need to charge and leave the cell to hold 2.7v for a few days. If it wont hold the charge its pointless going further. Once at 2.7v charge it at at least 10v with a cut off of around 3.65v. Dont just trickle charge it. iF its got an internal short then its never going to charge but will get hot. Once finish charge, note voltage an leave for a couple of days , note the voltage. If it goes down especially below 3.3v then its likely the cell is duff.
But the pack needs to be balanced. So if the rest are holding voltage, and that one is able to be charged. Discharge it at a high current to make sure it wil hold voltage (Put it in circuit with three otheres then run a 12v starter motor off them, watch the voltages)
Once you have established the cell is OK , you need to run them all down to 2.7v as a steady voltage. Then charge the pack as a whole. If one cell has been taken down as low as yours then its either got an internal short or the BMS is doing it. If the pack is balance. Personally I would junk the BMS. Your choice, and it depends if its controlling anything else, as if it does then you cant just take it out. Try and check each cell reading lines to see if there is any direct short between them that could bleed the cell down. It may just need a component level repair.
Good luck
Grumpy-b

ChrisBarron
Posts: 244
Joined: Tue Dec 11, 2007 11:26 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby ChrisBarron » Wed Aug 13, 2014 10:41 am

It is possible that that one cell was faulty from the start and therefore the very reason why you couldn't travel above 20mph. Once the whole pack is charged you can remove that one cell and see how it goes. Charging with a missing cell would cause an overvoltage problem across the pack, unless you can set the voltage of the charger to a lower value, or charge each cell individually, the latter being time consuming but as you're going to be testing the cells anyway....

Grumpy-b
Posts: 985
Joined: Sat Dec 01, 2007 12:06 pm

Re: Elecscoot E4 scooter with LiFePO4 cells

Postby Grumpy-b » Wed Aug 13, 2014 12:46 pm

Depending upon what the BMS actually does, it may have been turning off the charge early as a result of an over voltage cell (s).
Dont try charging the pack, you need to get the duff cell live or , give up on it and then check out the rest of the pack, if they are as unbalanced and under charged as I think they may be, using the pack could well take other cells low and cause further damage. Taking these cells low voltage under load (even just a bleed load will do it) causes bad damange and bloating, that bloating can then crush the cell beside it. That cell then has plates that are too close together, and under load can/will short. This can cause a melted cell (lots of pictures of these if anyone interested). Hence why dealing with a bloated cell is important. And a balanced capacity (Not finish voltage) pack is essential. The bloated cell also has greater distance between the plate surfaces which caused less capacity and early demise. If the cells are at all suspect, you will waste hours trying to get even a remotely balanced pack. Dont bother. Its really not worth it. Life is of more value than getting an under capacity pack to perform badly.
There are many other cells that could replace these, give better performance and be lighter. But at a cost. Replacing one duff cell is going to be hard, given that its probably 3 to 5 years old and a direct replacement no longer available.

Grumpy-b


Return to “Electric Motor Bikes”

Who is online

Users browsing this forum: No registered users and 3 guests