PINNED - Lithium battery conversion/info

[shirley_hkg]

CV stage. Balance unfinished.

[Burgerman]

Its still charging at 4A and stll balancing as 1 and 8 are high.

[shirley_hkg]

Damn, thanks for this info, appreciate it.

Looks like 8s eve-160 is really the only option for Permobil then?

.This CALB 187Ah (197 claimed) may fit a PERMOBIL

[robint]

OMG I'll have to ask my carer for the kiss of life soon. I am so befuddled by all this. They dont tell you all this when you join the Lifepo4 club do they.

When Joe Public really finds out about all this (as they have done with Lion Lipo in catastrophic ways). I didnt know you had to stay within 20-80% dod band or you cell life cycles drop dramatically

Odd when you think that old school Eneloop Nimh 2 Ah cells are very very safe (unless deliberately sc). They charge easily no bms or protection - stop when they get warm 45C (charger only has a crude PS and a current limit resistor and they last for years as per some of my power tools but they barely manage 50% Ah of equivalent Lifepo

Tricky Tesla cars - well I read somewhere that Musk HQ is actually getting all his cars to phone home with personal travel data from car trips. He also has the ability to control your car with updates and can shut down/immobilise your car if he doesnt like you - like your membership club dues havent been paid? Big Musk is watching you - creepy
Is that true

[Burgerman]

No idea. But musk is the opposite. He enables, doesent shut down free speech. Is for helping those that help themselves. If he did that to a single customer then tesla shares would half, people would be rather annoyed. So why would he? Business suicide.

But yes they do track you IF you dont tick/untick the relevant boxes in the software. But its to your benefit. The service you are paying for when you buy a tesla. Still the best EV at any price.

[Burgerman]

What you need to do is slow down a little. Allow some time to absorb all the info. Start at the beginning it isnt a race!

[robint]

What you need to do is slow down a little. Allow some time to absorb all the info. Start at the beginning it isnt a race!

You are quite right, I am spinning out of control like a catherine wheel firework

Just so I understand your world is this the type of chair you use

[Burgerman]

No. Thats not a wheelchair its a scooter. It drives like a car. It doesnt xero turn etc no use indoors. Worse the seering on those just sort of flops left/right.

[robint]

Hmm I wondered how the skid steer worked, ruin your shag pile

Which dealer do you suggest some crowd in Ely called platinum mobility? has a lot of chairs. last thing I need is a ex UPVC windows salesman giving me verbal KWIM.

Howver I looked at chairs something like this

My main concern is that it is transportable, breaks down into sub units<20kg and fits in a hatchback. Will it go up a pavement ramp 10 deg (I am 95kg)

I can look this up but am I in the right ball park?

[Superchunk]

Damn, thanks for this info, appreciate it.

Looks like 8s eve-160 is really the only option for Permobil then?

.This CALB 187Ah (197 claimed) may fit a PERMOBIL

Interesting, I can't seem to find stock anywhere, already went for eve-160, will try them out, I am worried about the continuous discharge rate since I drive up long steep ramps all the time though...

[Burgerman]

Wont be a problem with that Ah.

[Burgerman]

Howver I looked at chairs something like this

My main concern is that it is transportable, breaks down into sub units<20kg and fits in a hatchback. Will it go up a pavement ramp 10 deg (I am 95kg)

I can look this up but am I in the right ball park?

Depends what is impotant to you.
My list of essential parameters is:
120A R-net controller,
Colour Joystick,
6mph 4 pole motors,
Rear drive but with wide enough front caster track to allow a centre footplate to move back between them.Allowing the seat to be moved back to give a proper rear biased CG position.
Swing away joystick,
Wide comfy arm tops and arms that are solit enough to lift and transfer on. So not seat back mounted...
Power lift, tilt, recline, power centre mount footrest.
Group 24 batteries.

Now that means theres very few CURRENT chairs that are really any good. The latest one would be the Dietz one that just arrived in my kitchen.

The pics are on another thread.
Here: https://www.wheelchairdriver.com/board/ ... =2&t=12461

My last 4 chairs were these, ALL modified slightly to make them any good:

[Burgerman]

Thats 4 different full rehab chairs.
The lightest of these is 160KG
The heaviest is 190KG.

All basically the same bar a few details. All feel exactly the same, same seating position and options, same programming, same adjusted seating positions so that if blindfolded I would be hard pushed to tell the difference in use.

Theres more chairs... I have a BM1 that I still use to drive from, not shown, and a couple of older backup chairs. The ones in this post above are all in my bedroom or kitchen and charged, shiny, and ready to use.

I wouldnt take the one you linked to very seriously for my needs. Retail price of these four varies from around 9k to 14.5k.

All are modified a little. Or a lot. In order to make them all behave and feel the same! The Dietz is currently stock, bar a few adjustments needing simple tools. So far. Because that one is an NHS prescription chair I only intend using indoors or in the garden at home. So far untested.

[ex-Gooserider]

Question... I know in past discussion it has been said that the balance wires should all be the same length, but how critical is it really? The cable between the PL8 and the chair is easy to make the wires all the same length +/- a couple mm, but what about the wiring between the plug on the chair and the actual pack cells? Does it matter that much if there is a few inches of difference? Or if there are intermediate connectors in some of the wires but not others?\

Given that the currents in the balance wires are really low as the pack gets towards being fully balanced I have trouble seeing that it should really matter... I am assuming that I'm willing to have a few extra minutes for the charge cycle....\

ex-Gooserider

[Burgerman]

I am not sure it matters much, as long as they are not wildly different. Like feet.

[Burgerman]

Hmm I wondered how the skid steer worked, ruin your shag pile

It actually doesent work at all. At least properly. Wastes way too many Amps that the controllers cant provide. So casters...

Which dealer do you suggest some crowd in Ely called platinum mobility? has a lot of chairs. last thing I need is a ex UPVC windows salesman giving me verbal KWIM.

I dont recomend any.
I have bought new chairs on eBay, direct from sunrise, several online dealers, and built some literally from parts. As long as YOU know exactly what you want and why, the dealer doesent matter. But the price does. So I ring around.

Howver I looked at chairs something like this
My main concern is that it is transportable, breaks down into sub units<20kg and fits in a hatchback. Will it go up a pavement ramp 10 deg (I am 95kg)

Well there are no chairs that are any good that you can brak apart to put in a car in 20KG bits. And the rest is all debatable.

I can look this up but am I in the right ball park?

I think that you are going to need a lot more research. A proper chair, and thats a lot heavier than your limit, and non that come apart. And probably a real mobility style car. Anything else isnt practical. Well it isnt unless you are only playing at needing a powerchair! Your needs may be different to mine though.

[robint]

Thnx 10^6 BM I get the picture now. You call those Full Rehab chairs I get it

I get that you need a modified recovery car with hoist and that you are supported by an NHS scheme - an essential - as you couldnt rely on mickey mouse Mobility outlet shops and their trivial service support that we get in the scooter world. I equipped myself with my own workshop and have certainly needed it over the years as Mobility Scooters breakdown and there's nothing like a garage you can go to for help - you are on your own.

Ive had some very hairy experiences in the last 12 years.

I dont need most of that raise and tilt gear nor indoor use. The chair concept only caught my attention for a moment cos I thought it might break down into convenient subassys. The Invacare Bora for outside covered use does sort of ie seat (24kg) battery 2x75Ah LAB 20kg, motor base frame 45kg

I wanted to go down to shops/GP/clinic etc max distance 10km ret.

But I think I might stick with the crude Roma shoprider I have as it ticks most of my needs boxes

but as we say YMMV

I am properly enlightened and humbled by your adaptive needs and share common cause as able-bodied people dont understand impaired mobility till it happens to them - they normally talk fast and run away.

Now I must digest all that info you provided on LABS and Lifepos and distil the essence for a charging menu which I will pm you

Robin

OBTW re Musk Tesla policy - it reminded me of M$ and Windows updates. I got caught out last night and lost a whole tranche of data logging on my ZKE cos I had forgotten to disconnect wifi. So without my consent it did a night time update and closed my app. Its very difficult to control Window 11 update service, you can only postpone it. If I shut my laptop for a month and open up again, I have to endure an extended Win 11 start up could take 30 mins or more to install a shed load of fixes. Its what happens if you dont schedule a regular update at least once a week (I dont need for a workshop laptop). Think of Marvin the depressed robot in Hitchhikers Guide "Life, dont talk to me about Life" he was envious of the robot door closer.

[Burgerman]

You are using windows 11...
I find it unusable. Windows as a service and a crap interface.
Also you are using a dummy version of windows intended for consumers and it is pretty much all geared towards features, feature updates, all the metro app garbage that make MS money, signing in to microsoft etc.

So you really dont want that. Plus it does all these feature updates and keeps adding new stuff that needs updateing all the time too.

So I always use the LTSC 10 version. I have LTSC 11 too. But I is still garbage. This behaves like the old windows 7 does. In that once you turn off all the crap stuff that tries to phone home ec, and disable "defender" it just sits doing nothing all the time. So YOU drive it. Not the other way around. It doesent have normal updates, or the host of MS money makers or push you to use. It has a few apps that you can uninstall, and then once configured properly it just does security updates only.

And this is because it is intended for things like cash machines, air traffic control, banks, stock market and the almost identical IoT version of LTSC 10 alsohas a license and agreed updates that continues until 2032. Because its used as an embedded operating system in devices.

And obviously its free...
Same with office LTSC 2024, etc...

So dump 11. Or at least use LTSC version. But thats still got the crap interface.
And use LTSC 10 64, IoT instead...As I have been doing ever since Windows 64 IoT LTSC appeared. All the rest of windows is garbage!

[Burgerman]

The chair you are looking at doesent only lack the seating options that you dont need. But it lacks a decent power module (control system too weak for 6mph motors) and has matching weedy 2 pole motors as well. As such it has low torque and this makes it less controllable even after you try to reprogram it from hovercraft steering to be usable and go whare you tel it. It also means that its higher impedance. The motors need more volts, at the same current to reach any given torque level. And that means much less efficient regarding range too.

And the seat like all rear drives needs moving rearwards to get a sensible CG position and take mass off the caster wheels to allow it to steer and drive properly. Which requires a centre mount footrest to allow this change so the casters dont hit your heels when you sit further back.

This is what I see whan I look at it.

[robint]

OMG you are scaring me

You are using windows 11...
I find it unusable. Windows as a service and a crap interface.
Yes
Also you are using a dummy version of windows intended for consumers and it is pretty much all geared towards features, feature updates, all the metro app garbage that make MS money, signing in to microsoft etc.
Yes Yes

So you really dont want that. Plus it does all these feature updates and keeps adding new stuff that needs updateing all the time too.

So I always use the LTSC 10 version. I have LTSC 11 too. But I is still garbage. This behaves like the old windows 7 does. In that once you turn off all the crap stuff that tries to phone home ec, and disable "defender" it just sits doing nothing all the time.

So YOU drive it. Not the other way around. It doesent have normal updates, or the host of MS money makers or push you to use. It has a few apps that you can uninstall, and then once configured properly it just does security updates only.
Yes I remember those happy days XP W7

And this is because it is intended for things like cash machines, air traffic control, banks, stock market and the almost identical IoT version of LTSC 10 alsohas a license and agreed updates that continues until 2032. Because its used as an embedded operating system in devices.

And obviously its free...
Same with office LTSC 2024, etc...
I didnt know that

So dump 11.
Oh thats too scary for me - I only just manage to cling onto to w11 with work arounds
Or at least use LTSC version. But thats still got the crap interface.
And use LTSC 10 64, IoT instead...As I have been doing ever since Windows 64 IoT LTSC appeared.
Never heard of it unfortunately too late for me
All the rest of windows is garbage!
Yes Yes Yes Yes Yes

FWIW I still have a W7 laptop around on a shelf - I hate M$

[robint]

image_2024-08-13_143238792.png (229.7 KiB) Viewed 3670 times

The chair you are looking at doesent only lack the seating options that you dont need. But it lacks a decent power module (control system too weak for 6mph motors) and has matching weedy 2 pole motors as well. As such it has low torque and this makes it less controllable even after you try to reprogram it from hovercraft steering to be usable and go whare you tel it. It also means that its higher impedance. The motors need more volts, at the same current to reach any given torque level. And that means much less efficient regarding range too.

And the seat like all rear drives needs moving rearwards to get a sensible CG position and take mass off the caster wheels to allow it to steer and drive properly. Which requires a centre mount footrest to allow this change so the casters dont hit your heels when you sit further back.

This is what I see whan I look at it.

Thanx BM you have suitably saved me from a path of foolishness. It appears that the wheelchair world has just as much mickey mouse rubbish as the scooter world

I can only vouch for the group 3 TGA Sport rider and the Mini Crosser 4 as being capable well built kit (1300W motor) but heavy. The mini crosser with me on board weighs in at 250kg (100Ah LABs 80kg IIRC ca £450). The PM motor needs new brushes - but sadly the design is such that the motor is underneath and the whole assy has to be dismantled to remove the motor for brush replacement - bad design mistake. The TGA is all accessible by contrast.

I replace the cumbersome plastic hood with a small tarpaulin, for easy access in emergency. I replaced the monster executive seat with a crude bobber type lash up made with bed springs. It works very well on the rubbish uneven pavements we have which are very spine crushing and after 10 minutes you feel tortured. Pedestrians dont notice how bad they are. see how the motor bits are all easily accessible

Im surprised the Chinese havent come up with a light weight transportable 3 wheeler with Lithium batteries drive a pair of hub motors in the rear wheels oh plus a light weight bobber seat - they should ask me for a spec - and perhaps your good self for motor/battery spec. That would sweep the board (people who design these things are probably not impaired)

[Burgerman]

There are no direct drive brushless motors with adequate torque and control at the LOW speeds we need in a wheelchair for steering etc. They lack efficiency at super slow speeds so take huge battry currents at starting torque type speeds. Could be done with a scooter. Probably already is. Never looked.

[Burgerman]

Everyone when looking at lithium goes through this perod where they search for months and keep posting links to drop in lead brick replacement batteries.
Thise have been getting bigger. A few years ago a GRP24 sized one, to match a typical 75Ah lead brick was only around 50Ah.

Since you need to keep around 15 to 20Ah IN RESERVE with lithium or get caught out with a sudden dead stop, and no way to "limp home" that meant that thee were really only any daily use for 30 to 35Ah. So both more expensive and less reliable (due to the complexities of BMS and the undersized over worked cells, while achieving about the same range as the lead that they replaced. With the additional problem that under heavy loads (rehab chairs are heavy!, users are heavy) and with faster 4 pole motors, especially if acceleration was programmed to be lively, these things chopped of power regularly. Leaving you stopped suddenly.

So they were literally a waste of mone and highly problematic.

After about 7 or 8 years, the prices fell a bit and now 70Ah ones in the same case size appeared all over the place. Usually with the same problems, and a still high cost. But now they would actually give SLIGHTLY more range than lead. If you only kept 15Ah in reserve unused, which you really have to do. But at least they were now a match. (Remember that with a LEAD/gel battery, you only get to use about 40Ah maybe 45Ah before the thing stops. But wait a while and it will recover a little and usually gets you a couple of mile to safety. You cannot do this with lithium. When it stops you are up shit creek. So a 20% cushion for longevity and for not geting cought out is essential.) So if the 70Ah lithium was fitted it would ive a small gain in range. But the BMS was still very liklely to cause reliability issues at high currents. So these can work for some chairs that are lower speeds, or lightly programmed or used more gently. Provided the BMS doesent screw up anything!

Today there are now some bigger 100Ah ones available. (up to 135 in fact). These like the previous ones are all mostly using 1C rated cells and BMS. Meaning they can do 100A max discharge now. Thats about half what is needed for a heavily loaded chair with 4 pole motors and serious acceleration settings programmed in needs. But enough for most smaller slower chairs. And lighter users and mild acceleration settings. But many are also available with a short term "boost" capability so that it can deliver say 200A or 300A for 1 to 10 seconds. DETAILS MATTER HERE!!! So check the specs very carefully!!!

For e,g these ones on eBay, would be OK (provided that the specs are not like chinese horsepower figures. Or hifi amplifier watts figures... And they frequently are, I dont belive the chinese easily. ) And if the battery in the link can really do that 300A for 10 seconds (and the cell voltage doesent drop below the low voltage cut off limit under heavy load either and not enough detail here) then this woud work without cuting out even on my chairs with fully programming and wheelies.

But... Dont expect reliability as BMS are renowned for failing, dead mosfets etc and also for being crap at charging and treating cells well. So you will never get a long lifespan as claimed.

So choosen with care, on the right chairs, these can work and will almost double usable range with a small safe reserve.

But they will not come close to the sheer lifespan of several decades, or complete reliability of a BIG 230Ah pack charged with a hobby charger, or get close to the 500% range gain that these will allow. But at least SOME of them may be workable. Since the cost is now very low, comparable to lead, they are worth a go. Especially from amazon. As they will refund if they cause issues. As long as they are the supplier.

These for e.g. Cheap, 10 secs at 300A, and so shouldnt cause problems if it all works like it says on the tin. I might even test a set in the dietz chair.. It has lof current draw, as its NHS 4MPH... Just be warned that it might not woork out as cuddly as it would seem.

https://www.amazon.co.uk/gp/product/B0CQQF3W3B

[Burgerman]

Want to know how far a lithium battery will take you before buying?

Get a cheap hobby grade watt meter. I have a turnigy 130A one, like below. I fitted an anderson grey connector on the input and on the output.
It connects between the battery on your chair and the controller. LITERALLY plug and play in the true sense. Zero your phones sat nav position and miles. Or zero te chairs trip meter.
Set off with it all zeroed. Drive with your chair along or around your area until you get to the point where its flashing red lights and about to run out of juice... Or has done.

Read the watt meter (in Ah used) and also look carefully at the battery volts. Write it down. Look a the distance covered on the joystick or sat nav on your phone that day. Write that down too.


You will find that the faster the chair, the more hills, the faster it runs out of power. And the less the range is.
You will also find that a typical healthy 75Ah battery runs out and dies after a real approx 40Ah is used. At least to the point where the chair will still work. Not close to the 75Ah it is supposed to do. This is because of something called peukert as well as temporary voltage depression when you discharge it fast. And about 12 miles in 2 hours will be about the best you can do. Approx.

So if you get say 36Ah used, and maybe 12 miles, then you can do the maths and find how many Ah per mile. So in this case thats 36Ah div by 12 or 3Ah per mile. You now know that you get around 12 miles range from lead.
Thats a crap figure by the way. Many get more. I get less. So your new 230Ah lithium battery, divided by 3Ah (per mile) CAN do 76.66 miles. Or 60 real miles and still have around 16.6 full miles in reserve. Some 5.6 miles more remaining than the fully charged lead battery was even capable of to begin with! So that is a super safe figure. All you need do is never go further than a 30 mile away destination and back. Use the chairs mile meter and zero it every charge. No need to have any BMS, battery fuel gauge, or anything else to monitor it.

As long as you dont exceed your distance to a safe charge level on the joystick, you are safe.

Your figures may be better or worse depending on your use, your chair, your programming and your surroundings.

[ex-Gooserider]

<snip>

Tricky Tesla cars - well I read somewhere that Musk HQ is actually getting all his cars to phone home with personal travel data from car trips. He also has the ability to control your car with updates and can shut down/immobilise your car if he doesnt like you - like your membership club dues havent been paid? Big Musk is watching you - creepy
Is that true

Sort of... ALL modern cars do a lot of nasty privacy invading stuff, search for some of the detailed investigations done by the EFF and Mozilla folks that describe the incredible amount of data collected by the modern car (Hint, they listen to every world you say....)

If you have a newish car, you ARE being tracked, and your car IS phoning home, regardless of who made it...

Many of these cars (including Tesla) can have their software updated over the air, AND have various functions controlled remotely. The security on these systems are very poor, and several people have done demonstration hacks where they have taken over the systems of cars, so not only is Elon able to potentially hijack your car, it is at least potentially possible for ANY cracker with evil intent....

Enjoy your driving

ex-Gooserider

[Burgerman]

Quote, from EVLITHIUM today.

Hello John

The cell size is : 207.2*53.85*173.93mm
and we send you brand new A-grade batteries from the factory,
for the order of 8 230Ah cells welded terminals, the price of each battery cell is US$65
the shipping cost to your door by air is US$380,
if any questions, please feel free to contact us,
thanks and waiting for your reply

So 900 US dollars, or 680 UK pound.
I can get cheaper. But she swears that these are good, welded terminal cells, no swelling, never recovered or reused, all A grade and brand new with super low internal resistance.

Are EVlithium reliable?
What do you think?

Thats a delivered price and so not too bad.
Thats about double the cost of a set of decent deep cycle lead bricks.
For 5x the energy and range. Or the same as 10 lead bricks!
And not 1 years use, maybe 20 or so.

What other decent suppliers are there?

[Burgerman]

https://www.apexiummall.com/index.php?r ... uct_id=431

EU stock, are these reliable?

Shirley?
Can you do better or recommend reliable supply?

I was going to use dorcan but no stock.

[shirley_hkg]

I can't offer better protection than Paypal.

Abundant supply of cells now , so they need not to take risk . Reclaim your money if not as advertised.


https://www.wheelchairdriver.com/board/ ... TL#p196237

[Burgerman]

Well yes. However, 230Ah is now a discontinued size. So I am ordering a set while I can. Because nothing else fits as well...

So will be ordering soon. Out of stock in many places. All 280 308 310 etc now.

[Burgerman]

Evlithium
Dont use...
They will not accept PAYPAL or a Credit Card.

Sorry, we cannot accept the method you mentioned.
Our company regulations do not accept PayPal and credit card payments.
Generally speaking, some of our customers choose to use Trade Assurance to ensure their rights and interests, but you do not trust Ali.

------------------------------------------------------------
Abby Han
Evlithium LLC.
Phone/ WhatsApp: +86 13326321310
Wechat: 13326321310
Email : sales03@evlithium.com
Web: http://www.evlithium.com

These are the 2 safe ways to buy. In both cases they will refund if the cells are late to arrive, damaged, or NOT AS DESCRIBED.
There is only usiually one reason that a company wont accept these two payment methods. And that is that they cant. Because they have either been refused, or because they have had to refund a few transactions. In both cases that means they are not reliable.

So I would rather have bought from Docan Power. They are happy with both methods.

Currently shows as out of stock! Except in the US. So I emailed them.