Need clarification when charging with power supply like Mean Well

I’m looking for help on how to charge using Mean Well LED power supplies. I've done some reading and I think I know what I’m doing, but just need clarification on a few things.

Here are the details:
Battery: 24S1P, Headway 38120HP cells
BMS Purchased, not yet received – JBD 24S, 100A common port smart BMS https://srikobatteries.com/product/jbd-smart-lifepo4-24s-72v-100a-common-port-bluetooth-bms/

1. Is there an existing wiki on how to charge with a power supply?
2. There isn’t a Meanwell power supply with adjustable current and voltage that will go up to the 86.4 volts that I need as far as I can find. Please let me know if i'm wrong.
3. When series connecting an ELG or HLG Meanwell power supply, do I just simply connect the negative DC output from one supply to the positive output of the second power supply?
4. Suppose I want to charge to 3.5V per cell (lifePO4 cells), 3.5 x 24 cells in series = 84V. So I dial the combined voltage of the two series connected power supplies to 84 V. Do I just I check this with a multimeter?
5. When do you decide to pull the plug on the charging process? My understanding, the power supply starts in the constant current phase, and eventually reaches 84 V as the current drops. Do I just keep monitoring the power supply until it drops to about 3 % of the set current? So if the power supplies are set to 4 amps, do I just stop charging when I see the current drop to 0.12 amps?
6. What should I use to monitor the amps in the charging process. Something like this?: https://www.amazon.com/gp/product/B013PKYILS/ref=ox_sc_act_title_1?smid=A2EFSDTWMPHWEA&psc=1
7. I understand that leaving a lithium battery to trickle charge reduces its life, but if I’m only charging to 3.5 v on these lifePO4 cells, is that still the case? It’s not my plan, but if I can’t cut it off right away, is that a big deal?
8. Looking at the data sheet for something like the Mean Well HLG-150H-36A, it says the constant current region is 18-36v. But the voltage adjustable range is 33-40v. What does that mean for the current output between 36 and 40v? Does that just mean it can’t hold a constant current at that range? The rated current for this model is 4.2A. Does that just mean this will output something less than 4.2 A when adjusted to something above 36 V

Thanks all!

StinkyGoalieGuy said:

I’m looking for help on how to charge using Mean Well LED power supplies. I've done some reading and I think I know what I’m doing, but just need clarification on a few things.

Here are the details:
Battery: 24S1P, Headway 38120HP cells
BMS Purchased, not yet received – JBD 24S, 100A common port smart BMS https://srikobatteries.com/product/jbd-smart-lifepo4-24s-72v-100a-common-port-bluetooth-bms/

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1. Is there an existing wiki on how to charge with a power supply?

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Not a wiki, no, because the ES wiki doesn't exist anymore (hasn't been rebuilt yet).

There *are* a lot of posts and threads discussing it; many of them are findable by this search (it may not have the info in *my* post there, but it could be in another post in the same thread, so the search only lists them by thread).
https://endless-sphere.com/forums/search.php?keywords=meanwell*&terms=all&author=amberwolf&sc=1&sf=all&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

2. There isn’t a Meanwell power supply with adjustable current and voltage that will go up to the 86.4 volts that I need as far as I can find. Please let me know if i'm wrong.

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Not that I know of. But you can just series them.

3. When series connecting an ELG or HLG Meanwell power supply, do I just simply connect the negative DC output from one supply to the positive output of the second power supply?

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Yes. The AC inputs to both MWs are paralleled. MWs are isolated, including their casings, so they won't short anything out.

Set the current on both of them the same, to whatever the charge curretn you want is. (you can actually leave the current on one at max, and just adjust the second one down; they're in series so the second will limit both).

Set the voltage on each to half the total, to make it easy, if using two identical units. Or see below for alternatives.

4. Suppose I want to charge to 3.5V per cell (lifePO4 cells), 3.5 x 24 cells in series = 84V. So I dial the combined voltage of the two series connected power supplies to 84 V. Do I just I check this with a multimeter?

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Yes. Meter black on the most negative MW's negative output wire, meter red on the most positive MW's positive output wire. I recommend setting each one to half the total, if they are identical.

If you only need 84v, you can use non-identical ones, and save a little money. For instance, the HLG-600H-54A will do 54v max output (guaranteed; mine all go up to just under 58v). So you could use two of those, but you could also use one 54A and one 30A or 36A.
https://www.meanwell.com/Upload/PDF/HLG-600H/HLG-600H-SPEC.PDF
Depends on your specific choice of model as to which voltage range units to pick.

5. When do you decide to pull the plug on the charging process? My understanding, the power supply starts in the constant current phase, and eventually reaches 84 V as the current drops. Do I just keep monitoring the power supply until it drops to about 3 % of the set current? So if the power supplies are set to 4 amps, do I just stop charging when I see the current drop to 0.12 amps?

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You can, or you can use a monitor / cutoff board; I tried to find the post showing these but can't. I thought it was by Jonyjoe303 but I guess not. It was in some discussion similar to this one, IIRC.

Also...if you have a top-balancing BMS then you may want to verify the cells are actually balanced before shutting off the charger.

6. What should I use to monitor the amps in the charging process. Something like this?: https://www.amazon.com/gp/product/B013PKYILS/ref=ox_sc_act_title_1?smid=A2EFSDTWMPHWEA&psc=1

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I use my Cycle Analyst that's already on the trike; the MW I use is wired in permanently to the system on the controller side, so it counts charging like it was regen.

The one you link probably works too; never used that kind, but I"ve seen others use them in various threads here.

7. I understand that leaving a lithium battery to trickle charge reduces its life, but if I’m only charging to 3.5 v on these lifePO4 cells, is that still the case? It’s not my plan, but if I can’t cut it off right away, is that a big deal?

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You can use the monitoring circuit, or you can use a timer on the AC outlet (or the DC side).

Alternately, if your BMS is programmable for shutting off the charge input on cell HVC and what that HVC is, then once they've reached that it would shut off and it won't matter if your charger is still "on" or not.

8. Looking at the data sheet for something like the Mean Well HLG-150H-36A, it says the constant current region is 18-36v. But the voltage adjustable range is 33-40v. What does that mean for the current output between 36 and 40v? Does that just mean it can’t hold a constant current at that range? The rated current for this model is 4.2A. Does that just mean this will output something less than 4.2 A when adjusted to something above 36 V

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I don't know. On my HLG-600H-54A units, they maintain whatever constant current I had set in them thru the entire charging voltage range (which on mine is about 49v worst case minimum, up to 57.7v).

I haven't experimented with the HLG-150-12A unit I have; it's up on the backyard light pole driving a big LED panel so I can't go play with it to find out.


However, if you choose units based on the usable voltage range being within the constant-current region they list, so that seriesing them will add up to the total you need for full charge, you should be ok whether or not they maintain CC outside of that range.

Thank you, Thank you, amberwolf!

amberwolf said:

Yes. The AC inputs to both MWs are paralleled. MWs are isolated, including their casings, so they won't short anything out.

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Do the AC inputs have to be paralleled, or can they be plugged into the wall independently?

amberwolf said:

Also...if you have a top-balancing BMS then you may want to verify the cells are actually balanced before shutting off the charger.

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Good point, will need to set this correctly

amberwolf said:

Alternately, if your BMS is programmable for shutting off the charge input on cell HVC and what that HVC is, then once they've reached that it would shut off and it won't matter if your charger is still "on" or not.

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Ahh, yes, of course! That's a brain fart on my part. The BMS I ordered is supposed to be configurable for HVC... or so I'm led to believe

amberwolf said:

However, if you choose units based on the usable voltage range being within the constant-current region they list, so that seriesing them will add up to the total you need for full charge, you should be ok whether or not they maintain CC outside of that range.

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Very true, but I figure I could have more flexibility in choosing which units to buy and how I use them if I could figure out what they do outside the CC range.

CC-only is fine with LI, healthier in fact.

CV stage is a very small addition of actual usable energy input, especially at low healthy C-rates

and that is where stress occurs and top-balanced imbalance issues arise.

So just charge-to a V setpoint and stop.

An adjustable HVC circuit is best, terminating between 4.10-4.15Vpc is good.

StinkyGoalieGuy said:

amberwolf said:

Yes. The AC inputs to both MWs are paralleled. MWs are isolated, including their casings, so they won't short anything out.

Click to expand...

Do the AC inputs have to be paralleled, or can they be plugged into the wall independently?

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You can connect them however you want; even plug them into completely separate AC circuits (even to separate houses, if you happened to have the need to use that much power :lol: ).

The two I use in parallel for faster charging on the rare occasions needed have just one AC cord coming off the two, with them wired in parallel, so I only have to use one outlet for them (they don't pull quite 15A together even worst case on the 115vac I'm powering them from; if I was using htem on the 230v circuit it'd be half that current to get the 1300W+ total out of them).

amberwolf said:

However, if you choose units based on the usable voltage range being within the constant-current region they list, so that seriesing them will add up to the total you need for full charge, you should be ok whether or not they maintain CC outside of that range.

Click to expand...

Very true, but I figure I could have more flexibility in choosing which units to buy and how I use them if I could figure out what they do outside the CC range.

Click to expand...

Wihtout a graph to show, you may have to experiment.