electronics to convert Meanwell HLG supply into a charger

[teslanv]

On my latest charger I put diode inline on the output and it works, charger does not bleed down the pack anymore. My question was if these led supplies(with CC/CV) work the same way our chargers do to replace them with something posted above? Ip65, 5G shock proof, thermal, polarity safety is what I am after.
I gos some info that 600W are comming in august.

My builds are always with onboard charger therefore it is of importace to me that they were shock proof, splash proof, pasive coolled and with self reseting thermal safety as they get hot in enclosed environment. Above charger broke just 2 days ago because of the thermal issue. I will fit ot with 40C thermal switch no problem, but to have something ready made without tinkering is worth the extra they cost and I dont mind extra amp or two for charging

What's the spec of the diode? Seems like this would have to be rather large to handle the amps of a power supply.

 

[cal3thousand]

i am not arguing over a moot point. i am trying to clarify misinformation.

you guys feel like you can make any statement here that you wanna post up without any knowledge of what you are saying and this place is now full of misinformation that cannot be reversed because it is stuck in the wiki pages and all the posts full of misinformation about batteries and now about chargers too.

there is no editorial control here so it is not possible to stop the flood of misinformation and then people continue to argue something which is wrong and misleading to those who do not have the ability to know more than what is correct and what is not.

that is not fair to those who are trying to learn something and they are fed misinformation about charging voltages, battery capacity, BMS behavior, causes of the lipo fires, causes of why pouches puff, and on and on.

If you are trying to dispel misinformation, I would recommend explaining in detail the reason for your assertions. Simply telling someone that they are wrong does nothing for him nor the other interested and slightly-less-knowledgeable reader (such as myself).

For example, what components or design of the controller makes it such that the charger "diverts the balancing current around them through the shunt resistor". (What actually does this? And how do you know this information?) <---- those 2 answers included in your assertions will help it make MUCH more sense to the reader.

 

[madin88]

My question was if these led supplies(with CC/CV) work the same way our chargers do to replace them with something posted above? Ip65, 5G shock proof, thermal, polarity safety is what I am after.

Yes, they work the same way. Except of the problem with cut off when fully charged. Those chinese chargers (EMC, Kingpan, BMS Alloy shell) will cut off at about 3-10% of their rated current. The meanwells will hold the battery forever to the set output voltage until you pull them out of the socket.
I don't know if this is a problem, but i guess it is not good for our batteries.

Alan B has already built a charger out of 3 HLG 320: http://endless-sphere.com/forums/viewtopic.php?f=14&t=42169

 

[agniusm]

On my latest charger I put diode inline on the output and it works, charger does not bleed down the pack anymore. My question was if these led supplies(with CC/CV) work the same way our chargers do to replace them with something posted above? Ip65, 5G shock proof, thermal, polarity safety is what I am after.
.......

What's the spec of the diode? Seems like this would have to be rather large to handle the amps of a power supply.

The diode is Schottky 100V 10A TO-220

 

[heathyoung]

I can vouch that they work well as well - HLG-150-36 X 4 in series, with diodes across each one, and a diode in series with the output, that charges a 150V, 40AH pack on a Vectrix.

 

[madin88]

dnmun, why we can set the Full cut-off current point between 3-10% at all those EMC / AlloyShell / Kingpan chargers? Don't they stop charging at this point?

can you please give me an answer to this question?
As far as i remember they cut off when full charged (-> break connection to battery), but you say they do not.
Unfortunately i have the chargers here at my place, but no batteries so i cannot try it out until next week.

Normally these EMC chargers do have two pots for cut off setting:
one pot to set up when the led should turn into green (as an indicator), and the other pot for full cut off.

all BMSs will continue pushing balancing charge into the unfilled cells even as the full cells divert current around it. how many times do i have to repeat it.

please provide some serious evidence for your statement before you continue to say i do post misinformation here!!

 

[parabellum]

Those cheap, widely spread 3 trim pot alloy case Li chargers actually never "cut the charge", they just stop at the end of its CC/CV tunnel, where current stops flowing due to V equalization, holding the voltage and ready to continue charging. They switch on green led and off the fan at some point, but that's all.
This for example http://www.bmsbattery.com/alloy-shell/24-alloy-shell-120w-lifepo4li-ionlead-acid-battery-ebike-charger.html
I am not saying there is no other, switching off type.

 

[cal3thousand]

I have an EMC 1000 that has 5 trim pots

 

[izeman]

yes. the 4th and 5th are for coarse/fine amp and voltage adjustment. but basically it's three pots.

 

[madin88]

Those cheap, widely spread 3 trim pot alloy case Li chargers actually never "cut the charge", they just stop at the end of its CC/CV tunnel, where current stops flowing due to V equalization, holding the voltage and ready to continue charging. They switch on green led and off the fan at some point, but that's all.
This for example http://www.bmsbattery.com/alloy-shell/24-alloy-shell-120w-lifepo4li-ionlead-acid-battery-ebike-charger.html
I am not saying there is no other, switching off type.

the very small EMC chargers do have no relay like the bigger ones, so i guess they cannot cut the charge. The Meanwells HLG will act similar.

the question is: will it hurt the battery if the charger does not cut off?
If Yes: after what time (hours, days, weeks) and what happens with the battery in this situation?

 

[parabellum]

the very small EMC chargers do have no relay like the bigger ones, so i guess they cannot cut the charge. The Meanwells HLG will act similar.

the question is: will it hurt the battery if the charger does not cut off?
If Yes: after what time (hours, days, weeks) and what happens with the battery in this situation?

Have ~ 200 cycles on 2,5 years turnygy hardcases 15Ah 3P24S, about 80% capacity left. Always used those chargers (in 2P2S config), few times badboy charger. No BMS charge to 4.1/cell, DOD <80%.
My brother uses one on 2 packs 5Ah 1P12S made of same hardcases with BMS and almost all the times 100% DOD for 3 years. Have no clue about cycles but estimate 60-70% capacity left. He sometimes charges for days, forgetting about.
IMHO those batteries do not care about chargers duty or feelings, they care only about Voltage between cathode and anode. After it equalized with charger, there is no current flowing anymore, no matter hours, days or weeks passed.

 

[madin88]

IMHO those batteries do not care about chargers duty or feelings, they care only about Voltage between cathode and anode. After it equalized with charger, there is no current flowing anymore, no matter hours, days or weeks passed.

some very little current will always flow because of the self discharge / voltage drop.

 

[dnmun]

@ agnius: you can avoid using the diode in the output if you go cut the leg of the drain down resistor across the output cap. it is usually a 4700-5600 ohm resistor and usually more than 1/2 w too since they are draining current 24/7 when the charger is on. they are there to drain the voltage off of the output leads when the battery is removed for safety reasons. to prevent electric shock to idiots who might not know there is still voltage on the output caps after the charger is turned off without it. you can remove the led too if it has one, and there is no current drain after that.

you don't even have to remove it since it will be standing up next to the cap, just cut the leg where it bends over at the top.

 

[izeman]

the very small EMC chargers do have no relay like the bigger ones, so i guess they cannot cut the charge. The Meanwells HLG will act similar.

the relay is powered on by the battery. it's not there to cut power from the charger to the battery in a case off a full battery. so every time a battery is connected to the charger the relay is turned on. even with the charger not connected to the wall outlet. voltage/current adjustment is done by the chargers internal electronics. so if the charger "thinks" the battery is full (determined by the values you set at the pots) it just lowers the current, and totally stops the current once it hits final voltage if you got the little daughterboard installed (we are talking emc, kingpan etc chargers now). this is a safety feature for rc-lipo batteries that my not have a bms. if you remove this then you have a charger that outputs a little "final balance" current that can be handled by the bms to balance the cells. this current must be low enough so the bms can bleed off the current from the high voltage cells. but even if it is too high the bms should turn off the charging mosfets in case a single cell hits lvc - if this happens there will be no real balancing. in theory there still is some balancing, because charging will start again once the bms decides that it accepts some charge again and powers the charging mosfets. this of course is dependent on the type/make of bms you're using.

 

[madin88]

izeman, thanks for your explaination.

taken together in short: the EMC, Kingpan and similar chargers do stop charging (adjustable with the internal pot between 3-10% of CC), but the relay still holds the connection.

as for balancing:
IMHO it very depends on the BMS if a longer CV stage (very little final balance current) makes sense or not. If the BMS already starts to equalize at 4V or lower, the pack will be well balanced soon. If the BMS does not work till a cell hits 4.2V, a longer CV stage will be necessary for a well balanced pack.

 

[parabellum]

IMHO those batteries do not care about chargers duty or feelings, they care only about Voltage between cathode and anode. After it equalized with charger, there is no current flowing anymore, no matter hours, days or weeks passed.

some very little current will always flow because of the self discharge / voltage drop.

I do not think 1/1000C bidirectional current flows or 0.001V fluctuations, will have any effect on battery life, at least noticeable to human perception. Impact charging cells to 4.19V instead of 4.2V will be magnitudes higher. I prefer 4.1V/cell actually.

If the BMS already starts to equalize at 4V or lower, the pack will be well balanced soon

Are there cheap Bms's on the market doing this? Any link?

 

[izeman]

If the BMS already starts to equalize at 4V or lower, the pack will be well balanced soon

Are there cheap Bms's on the market doing this? Any link?

afaik those little smartbms are fully configurable and you can set voltage for balance start, and hvc as you like.

 

[madin88]

the smart BMS are nice, but i have not found them for more than 13s, 30A. these BMS also can be used only for battery balancing (without current limitation), but than no more hvc or lvc protection..
sadly the programming adapter is very expensive.

i have found a german supplier which i guess also offers programming: http://www.groetech.de/index.php?main_page=product_info&cPath=26&products_id=264

 

[izeman]

sadly the programming adapter is very expensive.

i could do the programming for you if you wish. i bought the adapter, but all my 3 smartbms died unexpectedly.

 

[dnmun]

they are junk. i do not understand why people wanna buy the cheapest junk for the most critical part.

there is nothing wrong with charging to full voltage of 4.2V so that is why the BMS is built to balance the cell at 4.2V.

just because there is the crowd hysteria, this group think, that charging to full voltage is bad that has developed here on this board, does not mean it is in any way valid.

there is no way to change the way people think once they have been misguided by people they think know more than them because of the way this place works. it is an open forum and anyone can say anything they want to and there is no way to stop the flood of misinformation.

 

[izeman]

@dnmun. it was never said that they work well. i just mentioned that there are some programmable bms. and i don't see nothing wrong to set the hvc and lvc to the voltage i want, be it right or wrong. there is no 'one fits all'.

 

[dnmun]

but my point is that you have been misinformed about each of these things and there is no way to overcome the continued misinforming of other people who come here in order to learn something.

there is no reality check or logical basis for the statements people make here so the flood of misinformation causes the newbie to think that somehow the crowd knows best. but it is just wrong.

so your continued reinforcement of this idea that the published and documented scientific literature is inaccurate just does more and more to denigrate any possible cogent logical and accurate set of information for people to use in making decisions.

 

[cal3thousand]

but my point is that you have been misinformed about each of these things and there is no way to overcome the continued misinforming of other people who come here in order to learn something.

there is no reality check or logical basis for the statements people make here so the flood of misinformation causes the newbie to think that somehow the crowd knows best. but it is just wrong.

so your continued reinforcement of this idea that the published and documented scientific literature is inaccurate just does more and more to denigrate any possible cogent logical and accurate set of information for people to use in making decisions.

Stop saying that people are misinformed without bringing backup. You do the exact same thing and becomes a pissing match about who can say it louder or more often. Bring your proof for once!

I'm going to believe Justin before I believe you, so look here. It's from Grin's Satiator brochure and it CLEARLY states "vastly improved cycle life if they are not fully charged to saturation all the time..."

So there is CERTAINLY a benefit to not charging to 4.2V. Stop saying otherwise until you have better proof or a better source to refer. Because otherwise, YOU are the spreader of misinformation.






Here's a blurb from Justin that seems to refute your statement that charge is routed around the high cells in a BMS, but rather the high cells are drained bled down:

Taken from here

The BMS has no role in the matter at all, other than to bleed down high cells if they are out of balance, which it should just do quietly in the background. The BMS doesn't control anything, it just cuts out if things are way out of whack which really shouldn't ever happen in normal usage.

Now, I see that you edited your post as you have not found corroborating evidence to prove that charge is "routed around the high cells"

 

[madin88]

The BMS has no role in the matter at all, other than to bleed down high cells if they are out of balance, which it should just do quietly in the background. The BMS doesn't control anything, it just cuts out if things are way out of whack which really shouldn't ever happen in normal usage.

thats how it is. i do not know any BMS for our usage which acts different.
A few years ago there was a RC model charger from the very good german manufacturer Schulze Electronic on the market, with a special balancer who did push charge into cells with lower voltage -> it didn't work well and they discontinued this method of balancing.
Another german charger manufactuer brought out the Pulsar Equal 12S power balancer. This balancer took charge from cells with too high voltage and put it in the cells with lower voltage. It is also no more available.
They all went back to the common and simple bleed down technique.

 

[michaelkramer11]

I can vouch that they work well as well - HLG-150-36 X 4 in series, with diodes across each one, and a diode in series with the output, that charges a 150V, 40AH pack on a Vectrix.

HeathYoung,

It sure seems like you know quite a bit about wiring these hlg's up in series to bulk charge lipo's. The pack i've got is a 16s15ah made from the hardcase lipo's. Anyways, i've been breaking the pack down into an 8s30ah pack to bulk charge with an HLG-320H-36a meanwell led power supply.

My plan is to get another meanwell to charge the pack without having to break it down to 8s. I've seen a lot of info on how diodes are needed and heard about all of the isolation stuff. I just haven't really seen any exact info on how the diodes need to be placed in the circuit and what exact diodes to use. I also am wondering if there is anything that needs to be done to isolate the supplies.

Thanks for any help!