PINNED - Lithium battery conversion/info

[expresso]

few others-

and the Wine - thats just a very good bottle


but the first picture is the way mines are in the tray - 13 inches long way

[expresso]

Good one -

[expresso]

just found my chair itself - the battery tray pulled out -

[Burgerman]

Read this and look at the pictures a lot of times.

The lead batteries are group 24... ALL group 24 are 171mm wide. 260mm long. And between 220 and 240 tall.

You are doing way too much thinking.

[Burgerman]

Read this and look at the pictures a lot of times.

The lead batteries are group 24... ALL group 24 are 171mm wide. 260mm long. And between 220 and 240 tall.

You are doing way too much thinking.

http://www.wheelchairdriver.com/BM-MK3- ... rchair.htm

[expresso]

yes i may be - but then again - i wasnt able to fit the PC1500 in there -

i seen that link before a while back - but i also like to keep the orange tabs on the bottom and top of the pack - not on the sides the way you have it

not sure i explained that correctly before - if that can be done - so when i pull the try out- its just like looking at the Lead - same fashion etc,

i feel its easier for me that way -

[Scollard]

OK expresso. So each battery is 10" x 8" x 6.75".

A 6x6 cell battery pack made with the 12AH Headway cells measures 9.5" x 9.5" x 6.85" (240mm x 240mm x 174mm). This is nominally smaller than a group 24 sized battery. If you measure your box, it should be possible to put 2 of these packs into the battery box.

[Burgerman]

Around and around we go!

yes i may be - but then again - i wasnt able to fit the PC1500 in there -

That's because a PC1500 is LONGER than a group 24 just at the top, and shorter by about 1 to 2 inches in height.

[expresso]

just saying that i was under the impression that the PC1500 would fit if you have 24s already - so my mistake for not double checking - each chair is different

i made them fit in the P222 se chair - the PC1500 - so no big deal - but in that chair - one battery goes in one way and the other sideways -

only reason that i was able to make it fit - had to force one down - didnt drop in - since then i like to double triple check to make sure - not blaming anyone -

[expresso]

OK expresso. So each battery is 10" x 8" x 6.75".

A 6x6 cell battery pack made with the 12AH Headway cells measures 9.5" x 9.5" x 6.85" (240mm x 240mm x 174mm). This is nominally smaller than a group 24 sized battery. If you measure your box, it should be possible to put 2 of these packs into the battery box.

my battery tray is 334 mm Long x 259 mm Wide - x 235 - 240 mm High - that fits two batteries perfect - very tight on the top by the posts -

Now it looks like it would fit - if you compare to your 240mm x 240mm x174 -

but the inches dosnt seem like it -

would this be in the same postion once built - or on the side - thats whats confusing me also - BM has it built and turns it on the side - so the orange blocks are on the side - i am looking to have the blocks on the top and bottom - maybe thats throwing it off - -

in the end - only way to know is to try it - with 36 cells - connect them and see if its correct - or just buy the blocks with 4 cells and i can see with my eyes then -

i have a thing for visuals - when i see something - i can then make more sense of it - most times -

[Burgerman]

maybe thats throwing it off - -

[BounderGimp]

OK expresso. So each battery is 10" x 8" x 6.75".

A 6x6 cell battery pack made with the 12AH Headway cells measures 9.5" x 9.5" x 6.85" (240mm x 240mm x 174mm). This is nominally smaller than a group 24 sized battery. If you measure your box, it should be possible to put 2 of these packs into the battery box.

A 6x6 cell pack would give a nominal voltage of approx 19.something? Did you mean to say an 8x6 pack, it would be a bit over 25v. OK, what did I not see?

[expresso]

OK expresso. So each battery is 10" x 8" x 6.75".

A 6x6 cell battery pack made with the 12AH Headway cells measures 9.5" x 9.5" x 6.85" (240mm x 240mm x 174mm). This is nominally smaller than a group 24 sized battery. If you measure your box, it should be possible to put 2 of these packs into the battery box.

A 6x6 cell pack would give a nominal voltage of approx 19.something? Did you mean to say an 8x6 pack, it would be a bit over 25v. OK, what did I not see?

this is going to be for a 24V chair - - i have decided if i do the whole chair - it will be one whole pack as BM shows - i see the benefit of that - all depends how it fits in my Tray - if i can make it fit - i will do the 72 Cells - if not then group 34 -
all depends how it fits in my space - i have a Seat lift on my chair - Tilt etc, if i have to force it in - then i wont do 72 - well see -

i placed an order for 8 12ah cells - thats for the Add on i want to try on my other chair - when i get them - i can see how they fit in person - will give me a better idea when i see it - i have been and am reading all the pages here - i feel i wont be able to do 6 high - but i could be wrong - not like i havnt been wrong in the past

either way - if not 6 - then 5 -

i will invest in the hobby charger - PSU - solder kit - crimper - etc, - what ever i need - when i go for the full chair -

i will double check with BM before i order any charger etc, to make sure i am getting the one i need and any other parts - cables etc, -

i am actually shopping for a Utiliy cart on wheels now to hold all this stuff when i start this project -

http://www.amazon.com/gp/product/B00FJU ... o_pC_S_ttl

hope something like this will work - i dont have alot of space for a large one - i am looking to have it hold - the charger psu - small solder - crimper, heat guy - the battery pack etc, - so i can keep all the tools in on place -

does this look like it can hold whats needed ? if anyone uses one

[Burgerman]

There comes a point where you have to give up re-explaining the same thing over and over.

[Burgerman]

A 6x6 cell pack would give a nominal voltage of approx 19.something? Did you mean to say an 8x6 pack, it would be a bit over 25v. OK, what did I not see?

At great risk of repeating myself for the hundredth time, 6x6 = 36 cells.
9 in parallel, x 4 in series = 12V nominal. (9x 12Ah = 108Ah). Gives one block.

Two Are required for 24V. It will fit any chair that takes a group 24 battery in its specs because a group 24 is specified as 260L, 173W, 225 high. Although the SPACE REQUIRED for height is specified as 240mm because it ensures that a gap exists for safety above the terminals. So while you need to measure the chances are pretty good that 240mm high will fit. Remember, no terminals to short out.

That gives a 171mm (173 with clearance) wide, x 240mm high, x 240mm long package. It leaves a wasted 20mm at the end that isn't used.

If you have group 27 batteries you can fit more Ah than that to great advantage since these are longer... (305mm) Allowing an extra row of cells. That's another 6 on each battery. This means 12 extra. But only 8 can be used. SO 4 extra on each pack allows you to have an extra 12Ah. So 108+12=120Ah. That's what I am fitting in my BM2...

[expresso]

There comes a point where you have to give up re-explaining the same thing over and over.

I understand - sorry i dont have an IQ of 160 or more - i am trying and the reason i ask alot - ok maybe i repeat myself when i dont get it - i want to understand - i just need it dumbed down a bit more maybe - - i dont think i am the only one -
reason that everyone is looking for a drop in - because we dont all get it as easy as others -

i am here so i can learn and feel good about trying it on a full chair - theres no question about it - i will be needing help - more if i start that project - and i hope i can still get it here - with out it - i wont be able to do it on my own -

just curious - how many users have done a full chair ? maybe would be nice to hear from them - to explain any issues they ran into or not - which model chairs - so others with the same chairs etc, have heads up on whats ahead for them

has anyone done a S646se Quickie chair with a seat lift and tilt - would love to hear how it worked out for them -

just an idea -

[Burgerman]

I realise all of that. But all of this is already repeated over many times in this thread. Every thing you need to know is already here.

If you want to fit a full lithium (and you should rather than doing an add on, its *exactly* the same thing, and equally difficult) then first you need to measure the height of what will fit. Get a bit of tree wood, cut it to 240mm exactly and see if it will go height wise!

Then come back. Then we can do the next question. Up till then there's no point. (it most likely will but you need to know for sure). If not we can look at different ways or different cells to maximise capacity and make it worthwhile. The difference between doing it with 5 cells and 6 cells high is huge in terms of % GAINED in range and service life.

An example.
Lets say you get 40 to 50Ah max out of the lead batteries And get 14 miles. 45 Ah div by 14 miles =
If you fit 104Ah that's 3.21 Ah per mile.
With 6 cells high, 108Ah that's 33 miles.
With 5 cells high x 12 = 60 cells - that's not divisible by 8 so you need 2 extra cells... Or use only 48 cells total. Meaning you only get 6 parallel. Or 6 x 12Ah. 72Ah. That's only 22 miles and a shorter service life, more frequent charging etc. In other words you lose 33 percent in range, and probably service life too. But only save a little initial outlay. So you really need to know.

[expresso]

i will do just that - the ADD on - i will do either way - i ordered the Cells and will do that for the P222se - i am only going to do ONE Full chair - and thats my new chair 646se -

when i get the 8 Cells - i will use that to measure the tray on the chair i want to do the full pack - - i am reading and will get back to you when i am ready for the next step or the first step on doing the full pack -

thanks - and i hope i dont come off bad when i post sometimes - writing and talking in person sounds different and dont want to come off as being upset at anyone - if anything i am upset at myself for not getting it as fast as others -

its getting there -

[steves1977uk]

just curious - how many users have done a full chair ? maybe would be nice to hear from them - to explain any issues they ran into or not - which model chairs - so others with the same chairs etc, have heads up on whats ahead for them

I have for one, with help from an ex-RAF engineer to build a 8s 5p 75Ah pack using the 40152S Headway cells. My conversion was fairly straight forward since I don't need tilt or lift, and the lead batteries were side by side in one box. I use a PL8 charger with a COOLICE PSU, and its not that hard to set up and configure. Been using a lithium battery pack for over a year now without any issues.

Steve

[Scollard]

my battery tray is 334 mm Long x 259 mm Wide - x 235 - 240 mm High - that fits two batteries perfect - very tight on the top by the posts -

Now it looks like it would fit - if you compare to your 240mm x 240mm x174 -

but the inches dosnt seem like it -

would this be in the same postion once built - or on the side - thats whats confusing me also - BM has it built and turns it on the side - so the orange blocks are on the side - i am looking to have the blocks on the top and bottom - maybe thats throwing it off - -

in the end - only way to know is to try it - with 36 cells - connect them and see if its correct - or just buy the blocks with 4 cells and i can see with my eyes then -

i have a thing for visuals - when i see something - i can then make more sense of it - most times -

Maybe you should go to Home Depot, get some styrofoam, and make two cubes 240 x 240 x 174mm to simulate the size of the battery packs and test fit these. That should put you mind at ease.

[expresso]

just curious - how many users have done a full chair ? maybe would be nice to hear from them - to explain any issues they ran into or not - which model chairs - so others with the same chairs etc, have heads up on whats ahead for them

I have for one, with help from an ex-RAF engineer to build a 8s 5p 75Ah pack using the 40152S Headway cells. My conversion was fairly straight forward since I don't need tilt or lift, and the lead batteries were side by side in one box. I use a PL8 charger with a COOLICE PSU, and its not that hard to set up and configure. Been using a lithium battery pack for over a year now without any issues.

Steve

i was thinking of those Cells also - i have 8 12ah cells on order already - will wait for that - and see if i can use those to try to figure out what will fit best and how -
sounds great you have a year already -

i will try to make it fit as much as i can - i dont want to cut myself short - as long as it fits - i do it - 72 cells - -

[expresso]

my battery tray is 334 mm Long x 259 mm Wide - x 235 - 240 mm High - that fits two batteries perfect - very tight on the top by the posts -

Now it looks like it would fit - if you compare to your 240mm x 240mm x174 -

but the inches dosnt seem like it -

would this be in the same postion once built - or on the side - thats whats confusing me also - BM has it built and turns it on the side - so the orange blocks are on the side - i am looking to have the blocks on the top and bottom - maybe thats throwing it off - -

in the end - only way to know is to try it - with 36 cells - connect them and see if its correct - or just buy the blocks with 4 cells and i can see with my eyes then -

i have a thing for visuals - when i see something - i can then make more sense of it - most times -

Maybe you should go to Home Depot, get some styrofoam, and make two cubes 240 x 240 x 174mm to simulate the size of the battery packs and test fit these. That should put you mind at ease.

i may just do that - will wait till i get the Cells i ordered in my hands - - i will just make a tray out of card board box the same size of my battery tray - i have 4 spare MK 24 sitting here - with the tray box i make out of card board and the cells when i get them in my hands - i have a visual then -

[BounderGimp]

A 6x6 cell pack would give a nominal voltage of approx 19.something? Did you mean to say an 8x6 pack, it would be a bit over 25v. OK, what did I not see?

I made the assumption that he meant 6 series x 6 parrallel, =19.2V, he was referring to the physical layout of the cells instead.

----------------------------
At great risk of repeating myself for the hundredth time, 6x6 = 36 cells.
9 in parallel, x 4 in series = 12V nominal. (9x 12Ah = 108Ah). Gives one block.

Two Are required for 24V. It will fit any chair that takes a group 24 battery in its specs because a group 24 is specified as 260L, 173W, 225 high. Although the SPACE REQUIRED for height is specified as 240mm because it ensures that a gap exists for safety above the terminals. So while you need to measure the chances are pretty good that 240mm high will fit. Remember, no terminals to short out.

That gives a 171mm (173 with clearance) wide, x 240mm high, x 240mm long package. It leaves a wasted 20mm at the end that isn't used.

If you have group 27 batteries you can fit more Ah than that to great advantage since these are longer... (305mm) Allowing an extra row of cells. That's another 6 on each battery. This means 12 extra. But only 8 can be used. SO 4 extra on each pack allows you to have an extra 12Ah. So 108+12=120Ah. That's what I am fitting in my BM2...[/quote]

[Burgerman]

Assumption. Or presumption. I do it too. It usually means:

The mother of all f*****s...

[BounderGimp]

Assumption. Or presumption. I do it too. It usually means:

The mother of all f*****s...

What? Don't get it.

Below says MK g27 length is 12.83 inches, = 326mm.

http://www.mkbattery.com/search.php?view=hme

[Burgerman]

Yes, I typed 305 instead of 325. Some say 330.

Each cell is 40mm inc block. So 7x 40mm = 280mm long. That will fit 6 tall 7 long cells.
8x 40mm is 320 so should also fit... So, 8 long x 6 tall is 56 cells. Two packs. So 112 altogether. 144Ah.

[expresso]

i will remove the batteries and use the Cells once i receive to really check for sure - the space i can use -

i can see 8 Cells x 6 high - - maybe i can see that will working - i have to check the tray again once i take them out of the chair - i remember the tray to be an exact fit for two 24s - and i have 4 of them - so i made a box same size that fits both of them

if it turns out that i can fit only 8 x 6 high - can that still work out to make a decent pack ?

[expresso]

the battery done in this way wont fit in my chair -

its too long - my batteries are turned to the side one behind another -

[Burgerman]

That's a 45V 13S pack...

You need 6 cells long. X2.
That's 240MM. Your GROUP 24 batteries are 260mm long. That means your 6 cell high, and 6 cell long batteries are 20mm shorter than your group 24 batteries...

That battery is a 3240Watt hour, 78 cell, 45 volt huge battery. It allows 3x the range, and 2x the speed of the 8.5 mph motors I use. So 16mph... 45 miles range plus. You don't need that.

[expresso]

i hope i am wrong with my measurements of the tray box -

mines shows 13 and half inches long - - which is about 334mm -

if each Cell is 40mm - that means only 8 would fit - - how many high - maybe 6 -

but only 8 x 6 - - i hope i am wrong -

when i say long - i mean the width of the battery - x 2 - which is i think 167 mm wide - each battery

it can be 240mm high - but the length of the box with the batteries in the tray is 334 mm - for both batteries total -

so 8 x 40mm gives me 320mm -

my cell count wont add up to 72 cells -