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Re: LiFePo4 for Permobil C500S

PostPosted: 04 Jul 2019, 13:00
by quadcopter
Thanks a lot. I will try.

Re: LiFePo4 for Permobil C500S

PostPosted: 06 Jul 2019, 22:13
by quadcopter
Please say if I understand charging correctly.
I connected power supply to PL8.
PL8 to my PC. Alligator clips from PL8 to MK 74Ah battery (the cable is 15A max so I'll low charging current to 15A).
IMG_20190706_234745.jpg
PL8 cables

I opened the file (Lead MK Gel SINGLE-12V BAT SB50) to free preset slot (it's 24th) on Presets tab.
PLv2_03.png
PL8v2 load preset

Updated presets.
Then chose the preset in dropdown on the Cells tab.
Next I have to press Start button. Right?
PLv2_01.png
PL8v2 start

How long will the charging take?

Re: LiFePo4 for Permobil C500S

PostPosted: 06 Jul 2019, 23:25
by Burgerman
About 9 hours. give or take.

Re: LiFePo4 for Permobil C500S

PostPosted: 07 Jul 2019, 01:19
by Dan
For peace of mind you can click on edit (just above the start button) it will bring you right to the preset you are using so you can check its settings. Also I would tick the Advanced Properties box in the top of the preset window.

Re: LiFePo4 for Permobil C500S

PostPosted: 08 Jul 2019, 22:04
by quadcopter
The charging took 8 hours.
I got these data:
MK 74Ah - charging PL8 graph - 20190708.JPG
MK 74Ah - charging PL8 graph

MK 74Ah - charging PL8 info - 20190708.JPG
MK 74Ah - charging PL8 info

As I understand the battery got 27 Ah.

Re: LiFePo4 for Permobil C500S

PostPosted: 08 Jul 2019, 22:18
by quadcopter
Also I want to charge my 2 AGM Everexceed 70Ah batteries (now I use them on my powerchair).
How should I charge them? One after one?

Re: LiFePo4 for Permobil C500S

PostPosted: 08 Jul 2019, 22:38
by Burgerman
In the advanced tab, remove the 8 hour time limit. SET C.V. TIME LIMIT to NONE.

Those batteries are nowhere near fully charged. They are VERY high impedance, old, or sulfated. Basically long past useful service life. They are going to need at least another 8 to 16 hours on chare looking at that graph. It should have dropped to a few fractions of an amp, around 70mA after 8 hours. And it should have charged initially at much higher Amps. Have you got a low power supply? Or is it set in the supply tab to a low input current maximum?

It ran into the CV time limit LONG before charge is complete. They have obviously never been properly or rather fully charged for a very very long time if ever.

Re: LiFePo4 for Permobil C500S

PostPosted: 12 Jul 2019, 22:22
by quadcopter
Burgerman wrote:In the advanced tab, remove the 8 hour time limit. SET C.V. TIME LIMIT to NONE.

Is it here?
CV_Timeout.jpg
PL8v2 C.V. Timeout

How do I know that charging is completed?

Burgerman wrote:Have you got a low power supply? Or is it set in the supply tab to a low input current maximum?

I have Revolectrix 1200W Power Supply.
IMG_20190407_120035_small.jpg
Revolectrix 1200W Power Supply

I set 'Charge Amps' parameter 15A because it max limit for my alligator clips.

Re: LiFePo4 for Permobil C500S

PostPosted: 13 Jul 2019, 00:24
by Burgerman
Yep there!

In the SUPPLY tab, be sure the input Amps is set to at least 25A, Probably best set to 48A and then will never overload the supply.


How to know when ended? It will say charge ended or completed I forget. It may take a long time. If those batteries do not ever end, after say 16 to 20 hours on charge. then you will have to set that 8 hour limit again for future charges, and set terination from 80mA to say 140mA instead. Some batteries and especially some abused batteries will never reach that 80A point de to sulfation etc. But they should.

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 09:53
by quadcopter
When I got all my LiFePo4 batteries (cells) what should I do?
Do I need to charge them separately or it's better to assemble them in a pack and charge/balance?
Do I need to discharge them?

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 10:08
by Burgerman
Charge each full, then assemble. If you do it the other way around it may take an awful long time to balance.
Then use it.

Or...
If you want to spend a week fully charging each one. Then removing 1Ah from each one exactly. Them waiting a month. Then recharging each ine individually and noting the exact mAh returned, so that you can assemble a pack that has each parallel group with very similar self discharge rates, then you can also do that. It will store for a few months better without getting as far out of balance. But not essential. New cells are all usually pretty close anyway.

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 20:06
by quadcopter
What profile should I use to charge my 176Ah batteries?

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 20:10
by Burgerman
Are we talking 1 at a time before assembly?
Or all at once and balancing them?
How powerful is your supply? (1200W?)

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 20:19
by quadcopter
Yes, 1 at a time before assembly.
Revolectrix 1200W Power Supply.

Re: LiFePo4 for Permobil C500S

PostPosted: 14 Jul 2019, 20:27
by quadcopter
Also I'll need profile to charge and balance all of them.

Re: LiFePo4 for Permobil C500S

PostPosted: 15 Jul 2019, 02:52
by shirley_hkg
Burgerman wrote:Are we talking 1 at a time before assembly?
Or all at once and balancing them?
How powerful is your supply? (1200W?)


I prefer an initial charge in series @24v UNBALANCED .

Then change to aligator clips to bring the low cells to 3.6V individually.

Faster and less assembly and disassembly .

Re: LiFePo4 for Permobil C500S

PostPosted: 15 Jul 2019, 05:57
by Burgerman
But that presumes that you understand what you are doing. And how to achieve that. I do the same personally. But it just makes it complicated if you dont have that experience/knowledge.

I also balance a big unbalanced pack in series,built, by watching the screens graph as I attach a resistance like a car headlamp bulb, across the high cells to assist the PL8 in its initial charge where/if needed.

Packs, choose the one closest to your Ah, zipped.
http://www.wheelchairdriver.com/PL8v2-P ... 4%20packs/

Single cells, zipped.

Re: LiFePo4 for Permobil C500S

PostPosted: 15 Jul 2019, 06:38
by shirley_hkg
Burgerman wrote:I also balance a big unbalanced pack in series,built, by watching the screens graph as I attach a resistance like a car headlamp bulb, across the high cells to assist the PL8 in its initial charge where/if needed.


I do that too, but always ran out of bulbs .
:lol: cheers

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 07:49
by quadcopter
So I'll charge every cell with LiFe Charge ONE 90 to 200Ah Cell.PS8 profile.
Then assemble them and balance.

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 10:57
by quadcopter
What I need to do to balance pack?
Do I need some other profile?

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 12:14
by shirley_hkg
Set charge volt at 3.48V , and start balance @3.4V .

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 12:27
by Burgerman
I would just use the profile as you have it, and charge. If you had all cells charged before assembly, it should be balanced and topped up in a matter of 30 mins to an hour. The normal charge profile balances the pack every time its charged.

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 12:49
by quadcopter
Sorry, not clear for me.
The profile (LiFe Charge ONE 90 to 200Ah Cell.PS8) is for one cell. Right?
How can I use it for pack?

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 12:58
by Burgerman
You cant.

Scroll up the page... Read this post properly.

viewtopic.php?f=2&t=8675&p=141144#p141023

Or click here http://www.wheelchairdriver.com/PL8v2-P ... iFePO4.zip

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 16:31
by quadcopter
Oh, I see thanks.
What is better for 176 Ah - 'LiFe PO4 1S 8S Approx 150Ah.PL8' or 'LiFe PO4 1S 8S Approx 200Ah.PS8'?
176 exactly between 150 and 200.

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 18:43
by quadcopter
One more question please.
Can I use Permobil original interconnection between cells (2 lead cells) for my LiFePo4 cells connection (I mean connect 4 and 4 cells)?
I doubt if my new 6AWG interconnections are long enough.
20190329_164642 - marked.JPG
swalker interconnections

IMG_20181008_162709 - marked.JPG
Permobil C500 batteries interconnection

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 19:25
by Burgerman
Either one, probably the150 Ah one. Set charge Amps to whatever you want or to make sense with your power supply. That cell size is OK with 30 to 40A.

You can use any cell interconnection, provided its substantial like your yellow ones.

Re: LiFePo4 for Permobil C500S

PostPosted: 16 Jul 2019, 21:05
by quadcopter
Burgerman wrote:You can use any cell interconnection, provided its substantial like your yellow ones.

I want to use 6 interconnections I made from 6AWG and 1 original.
This original is used in Permobil to connect 2 lead batteries. I think it's longer and made from other cable (maybe 8 AWG).
I read that it's better to have all interconnects have same length and area.
Does this longer/other interconnection can cause some damage?

Re: LiFePo4 for Permobil C500S

PostPosted: 17 Jul 2019, 06:16
by Burgerman
It ay cause the graphs in the PL8 to look less than perfect But the chair should work fine.

Re: LiFePo4 for Permobil C500S

PostPosted: 17 Jul 2019, 14:03
by quadcopter
I opened 'LiFe Charge ONE 90 to 200Ah Cell' and 'Termination -> C.V. Timeout' is set 2 hours.
Is it enough to charge 176 Ah cell?
Can I decrease 'Charge Amps' from 35Ah to 25Ah?