PINNED - Lithium battery conversion/info

[fishinjunky]

Do you guys think 8 of the 230ah cells I posted above will fit my box?

Box measurements:
Length: 342mm

Width:   291mm

Hight: 254


Also the cable in the pic with a label and fuses can I use a Anderson sb50 to connect it instead of having it " hard wired " like it is?

i wonder what those little fuses are for on your batteries - and that breaker looks large - 120A ? looking at the connectors RED ones - they look like SB50 - from the wire thickness - but hard to see for sure - looks different than mines - one of these days i want to open my breaker box to see what is in there for real -

SB 50 come in Red also - my other chair has the Red ones from sunrise - before then they had the black - i guess they dont do all of them the same then

will i remove the breaker box with the lead batteries. do i need to install the breaker back on the lithium batteries?

[fishinjunky]

what do you guys think about these specs on these 230ah cells?

[shirley_hkg]

They are all the same, used /under grade / return stuff etc . Just a matter of degree of imperfection.

However, they still can handle a wheelchair's need very well.

Don't expect genuine A grade new cells .

[fishinjunky]

They are all the same, used /under grade / return stuff etc . Just a matter of degree of imperfection.

However, they still can handle a wheelchair's need very well.

Don't expect genuine A grade new cells .

You were right they won't fit anyway I have 13.3 inches width and those are 13.8" inches when together. I'm having a hard time finding anything around 200ah that's under 173mm width . I'm nervous about my first purchase anyone have any recommendations I would like to fit as much AH in there as possible

[expresso]

measure your batteries that are in there now - - each one - and then look for cells that match that size

remember you can rearrange your cells also - they dont have to sit the same way - on my last pack - i put 6 in a room and two of the sides ways

they fitted in my stock battery tray which held group 24 lead -

[fishinjunky]

measure your batteries that are in there now - - each one - and then look for cells that match that size

remember you can rearrange your cells also - they dont have to sit the same way - on my last pack - i put 6 in a room and two of the sides ways

they fitted in my stock battery tray which held group 24 lead -

Nice. But its the two that are sideways is where I don't have room they are to long together 173mm x 173mm

[expresso]

Yes I know same for me. It was tight but I made it fit.

[fishinjunky]

Yes I know same for me. It was tight but I made it fit.

That's probably what I'll have to do also

[shirley_hkg]

Don't be limited by the battery box. It can be modified by cutting in halves , pull away a bit, and glue together .

You may not need the box at all.

Look into the actual battery compartment.

[ex-Gooserider]

Are anderson sb50 connectors sufficient for connecting lithium
pack to power module. And for connecting the pack to a charger for charging at up to 70amps. I have a 120amp joystick planning 200ah or 230ah pack.

SB50 and PP-75 Andersons use the SAME pins, only difference is the shells. The SB-50 / PP-75 connectors are fine for anything on our chairs. The 50 or 75 A rating (what the numbers refer to) is their ability to be "Hot-plugged" or connected under load safely. Once connected they can handle the same current as the wire they are attached to, which is AWG-6 (maximum) for these connectors....

ex-Gooserider

[wheelchairer]

.

so when you are only charging one sell it is just the positive and negative leads on the balance cable I should connect? so that would be for cables, the positive and negative off the balance cable and the positive and negative power cables, in total for cables. I don't logically see how it could be any other. Just doublechecking.

[Burgerman]

You dont need balance wires on 1 cell. Theres nothing to balance.

[fishinjunky]

Well its lithium time!!!

Just placed my order with the same person expresso recently ordered from. I got 8 x 202ah cells. They will be here in 2 weeks ( I paid extra for air freight because I'm impatient as hell )

Also ordered the components I need including a iCharger4010 duo
Hopefully the iCharger 4010duo will be a option for people that don't have a PL8 . But only time and proper testing will tell.

I feel confident in building the battery. I think I've asked the right questions and done months of reading and learning.

I'm going to start a thread once it's built to show how easy it is to do. But my advice to any beginners is start with the basics and learn and understand the electrical terminology and abbreviations.

The person I purchased the cells from was great! Very helpful and responsive. I'f the cells are good when they arrive then this seller is a definite winner.

Thank everyone for all your help. What a great circle of people on this forum!!

[shirley_hkg]

You dont need balance wires on 1 cell. Theres nothing to balance.

He said he couldn't read IR this way.

[Burgerman]

Oh. Well in that case...

[YellowBuzzaroundEX]

I read a couple pages of this thread. I read the part where you said drop in replacement lithium batteries don't have enough capacity and their BMS doesn't work well because it's in the wrong place.

Does your DIY system use a BMS in battery or in charger? Does your system use a BMS at all?

How does your system protect the battery cells from overcharging, overvoltage, and keep them balanced? Are you relying on the charger and balancing cable for protection?

I don't understand.

[shirley_hkg]

Can't believe you didn't know this at all.

https://www.wheelchairdriver.com/board/ ... f=2&t=6510

[steves1977uk]

I read a couple pages of this thread. I read the part where you said drop in replacement lithium batteries don't have enough capacity and their BMS doesn't work well because it's in the wrong place.

Does your DIY system use a BMS in battery or in charger? Does your system use a BMS at all?

How does your system protect the battery cells from overcharging, overvoltage, and keep them balanced? Are you relying on the charger and balancing cable for protection?

I don't understand.

The DIY build doesn't need a crappy BMS as a hobby charger will do the job much better and faster. The problem with most BMS's is that they overcharge cells and have a weedy balancing current which means it could take days/weeks to properly balance the cells if it hasn't already killed them.

Steve

[fishinjunky]

Do I have these settings right for charging my new pack with the ICharger 4010duo and the chair programming?

 

CHARGING 1S AT A TIME
PSU Current:  AC
Amps:   up to 40A
Volts:    3.650 (only for the first charge)
CV Time: 20 mins
Termination current:  40A (1% of 40A = 400mA)  /  30A (1% of 30A = 300mA)  /  20A (1% OF 20A = 200mA)  / 10A (1% of 10A = 100mA)
C-rate: 1
Number of cells: 1s

 

CHARGING 8S ( FULL PACK )
PSU Current:   AC
Amps:    up to 40A
Volts:     3.600
CV Time:  4 hours
Termination current:  40A (1% of 40A = 400mA)  /  30A (1% of 30A = 300mA)  /  20A (1% OF 20A = 200mA)  / 10A (1% of 10A = 100mA)
C-rate: 1
Number of cells:  8s

 

 DISCHARGING
Volts:  2.90 ( only for testing capacity or chair storage)

 

 CHAIR PROGRAMMING
Volts:  22v -25v
Motor compensation:   reduce by 5%

[steves1977uk]

They need to allow a manual Termination current as 400mA at 40A is way too high as it need to end around 1000th of C/1, so 230mA for a 230Ah pack for healthy new cells. Not percentages!

Steve

[fishinjunky]

They need to allow a manual Termination current as 400mA at 40A is way too high as it need to end around 1000th of C/1, so 230mA for a 230Ah pack for healthy new cells. Not percentages!

Steve

On the ICharger do I set the termination current as 1% of the charging current in mah
For a 200ah pack?

[Burgerman]

1 percent of what charging current?

[fishinjunky]

1 percent of what charging current?

20amps or 40amps

[fishinjunky]

1 percent of what charging current?

I'm sorry forget what just said I was brain farting it was 1/1000 of 230ah
Is 230mA what I would set as the termination point ?

[Burgerman]

Well on a PL8 I would set say 600mA as a starting point for the value called termination current. And thats independent of charge current. But you cannot do that on the ichargers.

They like most hobby chargers try to dumb it down which works sort off on hobby lipos. But not well on LiFePO4 packs esp on large sizes.

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

So if charging at 10A then 6% of that would be 0.6A (or 600mA)
So if charging at 20A then 3% of that would be 0.6A (or 600mA)
So if charging at 30A then 1.5% of that would be 0.6A (or 600mA)
So if charging at 40A then .75% of that would be 0.6A (or 600mA) BUT you cant set that below 1% so set it to 1. And test. Its not that critical. Aim for:

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

Either way, setting this correcty means you must do a little maths and the charge Amps changes the termination current. Stupid but it is what it is.

[fishinjunky]

Well on a PL8 I would set say 600mA as a starting point for the value called termination current. And thats independent of charge current. But you cannot do that on the ichargers.

They like most hobby chargers try to dumb it down which works sort off on hobby lipos. But not well on LiFePO4 packs esp on large sizes.

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

So if charging at 10A then 6% of that would be 0.6A (or 600mA)
So if charging at 20A then 3% of that would be 0.6A (or 600mA)
So if charging at 30A then 1.5% of that would be 0.6A (or 600mA)
So if charging at 40A then .75% of that would be 0.6A (or 600mA) BUT you cant set that below 1% so set it to 1. And test. Its not that critical. Aim for:

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

Either way, setting this correcty means you must do a little maths and the charge Amps changes the termination current. Stupid but it is what it is.

Ok now that helped. Thank you

[fishinjunky]

Well on a PL8 I would set say 600mA as a starting point for the value called termination current. And thats independent of charge current. But you cannot do that on the ichargers.

They like most hobby chargers try to dumb it down which works sort off on hobby lipos. But not well on LiFePO4 packs esp on large sizes.

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

So if charging at 10A then 6% of that would be 0.6A (or 600mA)
So if charging at 20A then 3% of that would be 0.6A (or 600mA)
So if charging at 30A then 1.5% of that would be 0.6A (or 600mA)
So if charging at 40A then .75% of that would be 0.6A (or 600mA) BUT you cant set that below 1% so set it to 1. And test. Its not that critical. Aim for:

600mA termination may be too high. You need to montor a few charges and aim for CV time of fully balanced with negligible balance current still occuring, + 15 to 40 minutes.

Either way, setting this correcty means you must do a little maths and the charge Amps changes the termination current. Stupid but it is what it is.

Ok now that helped. Thank you

So if I'm charging at 40amps I set it at 1 percent of that (400mA) then test

Or if charging at 10amp I set at 4 percent of 10 amps 400mA

[fishinjunky]

They need to allow a manual Termination current as 400mA at 40A is way too high as it need to end around 1000th of C/1, so 230mA for a 230Ah pack for healthy new cells. Not percentages!

Steve

On the ICharger do I set the termination current as 1% of the charging current in mah
For a 200ah pack?

If charging at 20amps I can set to 1.15% of that (230mA)

[Burgerman]

Then thats a good point to start. I thought it only did full percents.

[fishinjunky]

Then thats a good point to start. I thought it only did full percents.

That may be true as I haven't received it yet but wanted to get the math right. Be here next Friday.

If that's the case then should I start with 20a set 1% (200mA) ?