PINNED - Lithium battery conversion/info

[Burgerman]

http://uk.farnell.com/norcomp/680s13w31 ... dp/2294339

http://uk.farnell.com/norcomp/680s13w31 ... dp/2294339

http://www.store.revolectrix.com/Produc ... sion-Cable

http://www.store.revolectrix.com/Produc ... Plug-Cable

http://www.ebay.co.uk/sch/i.html?_from= ... =&_sacat=0

Balance wire (for battery - chair - side:
http://www.ebay.co.uk/itm/351091757644? ... EBIDX%3AIT

I used 5.75 Amp size here: All in red...


Manufacturer: NORCOMP
Order Code: 2294341
Manufacturer Part No 680S13W3203L401


Manufacturer: NORCOMP
Order Code: 2294339
Manufacturer Part No 680S13W3103L401

Search the part numbers for cheapest local supplier... REALLY not cheap, but extremely good quality. You better make a good job of it!!!

Don't forget to get two 25 pin metal sub D shells.

http://www.canford.co.uk/Products/20110 ... try-nickel

Allows 40A charge, and has enough small pins for your 9 balance wires with some spare. So one connector good for 8 cell battery. If you are 45 or 48V you need two cables.

Shells:
http://www.ebay.co.uk/itm/390997433597? ... EBIDX%3AIT

Sleeving:
http://www.ebay.co.uk/itm/290814495525? ... EBIDX%3AIT

Heatshrink - quality, glue lined:
http://www.ebay.co.uk/itm/Black-Adhesiv ... 2a2885b834

[Burgerman]

Connector wiring pin detail

Where 2 large pins are used for charge current.
9 small pins used for balance connectors.

Leaving 1 small, and 1 large pin unused.
These could be linked on the charge lead, to provide a circuit that closes when you plug in, to switch of the chair via its inhibit system if you wish to stop it driving while on charge.

Where 0 is the POS on the balance connector on the charger. And 8 is the NEG end of the ribbon.

[Burgerman]

Or http://www.wheelchairdriver.com/BM3-con ... le-40A.jpg full image.

[Burgerman]

http://www.wheelchairdriver.com/BM3-con ... nector.jpg Full image... If your screen is small.

[ex-Gooserider]

Looks like a nice build.... I might have been tempted to get different wire colors (makes it easier to verify or work on later) and I'm still of the opinion that banana plugs are not desirable (even 'safe' ones) so I'd be inclined to do surgery on the charger to replace the banana jacks w/ Andersons... However that is mostly detail stuff...

ART

[flagman1776]

I am using the 2 plug system (power leads plus balance leads) which I think will be more flexible over future devises... but I can see great value in the one plog approach if one must rely on a carer to plug in to charge. Just simpler.

[Burgerman]

These incidentally are the same connectors used on Invacare GB Motor setup and wiring loom.

[nandol]

John.why you didnt use headway 15A in bm3 ? obg

[nandol]

John.why you didnt use headway 15A in bm3 ? obg

[Burgerman]

Too long...

[nandol]

John,my new bm3 bat.box has 18cm internal width...15A fit,i think ? JUST HAVE TO POLISH 2mm at HOLDERS...?

whats odyssey pc1500 maximum width ? obg

http://www.evassemble.com/index.php?mai ... gh39pit9a6

[Burgerman]

Battery area in the centre section should be 174mm. That allows for 12Ah cell, plus orange building blocks, and connecting plates, 6mm allen screws, and a plastic/nylon insulating plug to fit between the sides without a massive short circuit and a fire!

(172 with screw tab)

[nandol]

and a plastic/nylon insulating plug to fit between the sides without a massive short circuit and a fire!

John,please post a pic of that PLASTIC-NYLON for me understand better.obg

[Burgerman]

The plastic orange blocks hold the cells. That's 172mm (+/- 1mm)

The end screws, are all X heads. These are hopeless, throw them away. Buy cap (allen) head bolts. Fit every one with a nylon cap as per the image. So if one comes loose, it cannot touch the metal centre section sides and cause a short circuit. They are all live!

[Lord Chatterley]

and a plastic/nylon insulating plug to fit between the sides without a massive short circuit and a fire!

John,please post a pic of that PLASTIC-NYLON for me understand better.obg

The exposed live terminals of the Headway cells will touch the sides of the metal battery box - so you need some sort of nylon or plastic insulation to prevent a short circuit. Do you understand? Say 'no' - if you do not understand.

This is very important.

Can you provide some jpegs of your battery box?

Obg

LC

[flagman1776]

The thin plastic hold offs on the orange spacer blocks are intended as a safety devise to prevent shorted terminals. The plastic caps BM shows are a double safety & I applaud that. Or a sheet of a non-conductive material could be installed inside the box. Better safe than sorry.
It would be a b*tch to short out our chair after putting so much work into it.

[Burgerman]

BEFORE CAPS BATTERY PAGE
http://www.wheelchairdriver.com/BM-MK3- ... rchair.htm

BEFORE CAPS PICTURE
http://www.wheelchairdriver.com/images- ... ry-700.jpg

AFTER CAPS
http://www.wheelchairdriver.com/BM3-con ... medium.jpg

AFTER CAPS
http://www.wheelchairdriver.com/BM3-con ... air-11.jpg Even bigger and clearer...

Notice the screws in the ends of the headway cells each have a black nylon hammered in CAP designed for the allen screws.
There are 78 cells. So there are some 156 caps to hammer in! CHECK EVERY BOLT IS TIGHT before you do this. Most people miss a few and have balance problems.

These are available as trim parts for motorcycles, cars etc. They are a tight fit into the head of the bolt. If the screw comes loose, it still cannot touch the metal sides of the centre section.

[nandol]

obg fellas...with 180mm internal bat.box i might stick 15A headways (just have to cut 2/3mm of does Orange pics,on each side)
next monday i`ll contact a tech college 120km norte of lisboa to see if the engineer and teacher can help me out doing assemblage...ivanov no compreende much about litio

[Burgerman]

180 not enough.

[Burgerman]

Apart from 180 meaning the actual terminals will touch, the blocks will all need to be trimmed down, and they are also taller so 42mm? per cell rather than 40 with the blocks.

For 24V 108Ah you need a battery that is 72 cell.

72 means 72 12Ah cells. And 108Ah. (more than double+ your old battery).

That's 6 cells tall, and 12 cells long.

That's 6x 40mm tall, and 12x 40mm long.

This means you need to measure carefully for a battery that is 240mm tall. And 480mm long. And 173mm Wide.

_____________________________________________________

My battery is 13x 40mm long. And 78 cells. So is 520mm long.
If you have 520 long space you could fit 2 extra cells on the top, for 80 cells total. Under the seat.
That means you could build an 80 cell 120Ah battery...

[steves1977uk]

What sizes are the cable sleeving? And would 12 core trailer cable be ok for the balance cables on the chair side to the female connector?

I have some 8 awg silicone cable that I'm currently using for the charge cables, I'm guessing this would be too big for the power pins on the 13 way plugs?

Steve

[Burgerman]

Trailer cable too heavy. You wont get it into the connectors with a couple of 12 gauge charge cables. Use the same stuff the balance wires are made from or very slightly larger. Use silicone charge cables. EBay. Use 12 or 15mm sheath and large heatshrink... Use inline fuse inside heatshrink soldered in the charge cables. Or just be careful...

And much care and thought and work neat!

http://www.ebay.co.uk/itm/Braided-Sleev ... 0088799839

[nandol]

and a plastic/nylon insulating plug to fit between the sides without a massive short circuit and a fire!

John,please post a pic of that PLASTIC-NYLON for me understand better.obg

The exposed live terminals of the Headway cells will touch the sides of the metal battery box - so you need some sort of nylon or plastic insulation to prevent a short circuit. Do you understand? Say 'no' - if you do not understand.
This is very important.
Can you provide some jpegs of your battery

yep,got it

[shirley_hkg]

For. nandol ;

viewtopic.php?f=2&t=4827&p=64872#p64872

[maker102]

The guy I have helping me with my conversion is on vacation for two weeks. I just got the batteries in yesterday and am chomping at the bit to get started. With me having to let the batteries set for at least two weeks I am going to try to get them Charged. I would appreciate it if someone could look over and tell me if I have all the setting correct. I plan on charging them 6 at a time positive to positive, neg to neg for all 6 batteries. I will be using the EOS Hyperion 1420 iNet 3 charger with the following setting:

Battery Type: LiFe
Cells: 1 each 3.3 volt Cutoff Timer: 300
Battery Capacity: 120000 mAh Pre Peak Delay: Not Applicable
Charge Current: 20 amps Trickle Current: Not Applicable
Discharge Ampere: 3.0 TCS Capacity: 100%
Discharge Volts: 3.6 TCS End Action: Continue
Peak Sens: Not Applicable TVC Adjust Voltage 3.600: 0 mV
Cutoff Temp: 50 C PB Batt Float Voltage: Not Applicable
PB Batt Charger Voltage: Not Applicable
Set Store %: 60

Thanks Carl

[Burgerman]

If you have the patience charge one at a time. After charge ends, leave on charge after the end as it beeps at you for 30 mins.
Set:


Battery Type: LiFe
Cells: 1 each 3.3 volt Cutoff Timer: OFF
Battery Capacity: 12,000 mAh Pre Peak Delay: Not Applicable
Charge Current: 3 amps Trickle Current: Not Applicable
Discharge Ampere: 3.0 TCS Capacity: 100%
Discharge Volts: 3.6V TCS End Action: Continue
Peak Sens: Not Applicable TVC Adjust Voltage 3.600: 0 mV
Cutoff Temp: 50 C PB Batt Float Voltage: Not Applicable
PB Batt Charger Voltage: Not Applicable
Set Store %: 60

Or GROUPS of them together in parallel, and adjust capacity from 12,000mah to 12,000 x however many cells in a group. As its faster.

Then immediately separate every cell. And number them. And store them for a week or longer.

Then charge 1 at a time, set to 12,000mah and see how many mAh you get back into each one. It will not be many. Maybe 10 to 100mAh before they are full again.

Group them together so that all these mAh figures add up to the same in each parallel group of cells so that the same amount of total mAh will be lost when sat in storage. This way subsequent balancing will be faster.

[shirley_hkg]

HEADWAY site is still selling obsolute 3.85V over-charge protection BMS.

[Burgerman]

As are many other places. That's just a reseller/battery dealer.

I use 3.55v, there is absolutely nothing up there apart from killing cells fast. The only reason they suggest 3.65 charge voltage is because it is an overcharge. That naturally balances cells slightly, helping the crappy 100ma BMS balancers out there. That one doesn't even reach 40ma until the cell is at 3.7V! It will certainly help battery sales!

You may also notice they have continual balance and not just above 3.4v which unbalances the pack in the middle all day long, And the balancer takes a small current from one set of cells continually to power itself. Best to throw them away.

Most current hobby chargers have 1 to 3 amp balance.

[intransient1]

Hi Burgerman,
I would be very interested in lithium battery conversion, I am lucky if I get five miles with mk agm.
Thanks intransient1

[Burgerman]

What size AGM? If these are full sized GRP 24s they or the chair have/has a problem.
I am fat! And get about 14 miles before they stop... (6mph chair)
Or are you just driving 5 miles and looking at a few lights gone out?
Maybe they are defective. Maybe the chair has a problem. Maybe they are not charged correctly.

73Ah? You ACTUALLY get around 45Ah from a set of those before you stop. (Look up Peukert, and voltage drop under load due to resistance and surface charge). MK gel specs here. AGM is a bit worse. http://www.wheelchairdriver.com/MK3.pdf
Or 140 Mins at 25A before dead (10v). But your chair stops well before this due to low voltage.
A 6mph chair takes 16 to 20A at 6mph if its healthy - so it should run for 2 hours and a half. (at 6mph that's your 45Ah used up). And so approx. 16 to 18 miles. If you don't get this you have a problem. (Hills, grass, lots of turning, flat tyres, or puncture free tyres, all have a detrimental affect.

You can get the full 108Ah from a 108Ah lithium pack, (72 headway cells) and so get 108 div by 45Ah = 2.5x the range.
Its actually possible to fit 120Ah (80 cells) too. That's 120Ah or about 3x the range. So 40 to 50 miles.