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Help with finding high amp charger.

kromc5

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I'm on the second charger that does not work, purchased a 40 amp dedicated lifepo4 charger and it does not perform to specs.

I found one similiar mentioned in another thread but the reviews were less than stellar.
 
I have been bumping my head on this topic too.

I might get the Victron 20A waterproof charger as a plug it in and forget about it unit.

I really like PowerMax charger.
I bought the PM3-55-LK

the LK is important, this allow you to set the voltage.


Battleborn batts have video that says it is ok to use,
I am confused about the settings a bit.

I am guessing you still use the 3 stage charging profile but as a LOWER boost/Bulk voltage?

I don't like the timed setting for the stages, but their manual is very vague.
 
I contacted my battery manufacturer and they told me which charger. In my case, its a NOCO Genius G26000 12V/24V 26 Amp Pro-Series Battery Charger and Maintainer , which is less than you need. I am thinking of purchasing a Powermax Converter Battery charger. I'd use this while the batteries are in the RV, and they come in models up to 90 amps. I'm also considering getting a DC Power Supply to charger the batteries.

Problems with specs I noticed. I have a 4 amp, 4 station charger, but there's only 1 amp to each station. On the 12/24 volt 26 amp charger, its 26 amps at 12 volts, but 13 amps at 24 volts. This means I can only charge two batteries at a time. Its not that these numbers are not in the manual, but usually in the small print, and not on the website I purchased them from.
 
I am not a fan of noco at the price they usually sell, on BF half price special, yeah sure.

I want clarity as to what the fluke a charger will do. If you want something that will last, I would suggest getting one with a fan :).

How big is your batt? 12v?

I am guessing from your 2nd para you have 48v pack? 4 12V?


PowerMax - Float @ 13.6 is something you need to consider.

My batts will something mobile and charged while they are being attended in my home office room. I doubt I will hook up a charger to them 24/7.
 
I am not a fan of noco at the price they usually sell, on BF half price special, yeah sure.

I want clarity as to what the fluke a charger will do. If you want something that will last, I would suggest getting one with a fan :).

How big is your batt? 12v?

I am guessing from your 2nd para you have 48v pack? 4 12V?


PowerMax - Float @ 13.6 is something you need to consider.

My batts will something mobile and charged while they are being attended in my home office room. I doubt I will hook up a charger to them 24/7.
I was tired last night and just noticed I did not even put in requirements, I'm trying to top balance lipeo4 cells. So far first charger was a 10amp and only does 1.9, went to a much more expesive dedicated 40amp that only does 2.5amps and sounds like my heat gun while doing so little.
 
I was tired last night and just noticed I did not even put in requirements, I'm trying to top balance lipeo4 cells. So far first charger was a 10amp and only does 1.9, went to a much more expesive dedicated 40amp that only does 2.5amps and sounds like my heat gun while doing so little.
How big are your cells?
 
I was tired last night and just noticed I did not even put in requirements, I'm trying to top balance lipeo4 cells. So far first charger was a 10amp and only does 1.9, went to a much more expesive dedicated 40amp that only does 2.5amps and sounds like my heat gun while doing so little.
My Riden 6018 works very well. Only 18 amps, but very nice.
 
I was tired last night and just noticed I did not even put in requirements, I'm trying to top balance lipeo4 cells.
I can edit your original post if you like, you might get more relevant responses.

So far first charger was a 10amp and only does 1.9, went to a much more expensive dedicated 40amp that only does 2.5amps and sounds like my heat gun while doing so little.
Sounds like you have a bigger problem than cheap chargers. Cheap low current power supplies are.. well.. low current :) but they shouldn't be that low, at least not until the CV phase towards the end. And 40A is far from low current. If two separate power supplies 1 x 10A and 1 x 40A couldn't hit 3 Amps it feels like there may be some other issue going on here (or maybe you just got very unlucky and received two defective power supplies).
 
My 40A AC to DC Bench power supply will start by outputting 40A @ 3.6V (varies depending on voltage of the actual cell) Constant Current then eventually it will flip to CC Constant Current at which time the amps pushed to cell start to drop slowly till the cell tops @ 3.65V and amps drawn trickles down to <2.0A.
Using a TekPower TP1540E as a Bench Powersupply. TekPower TP1540E DC Adjustable Switching Power Supply 15V 40A Digital Display

You linked to a TP1560 Which is the next up from mine. Mine works well (after I opened it and plugged in a loose connector).
The dials are touchy or finicky. Turn current to full, then dial-up voltage. Note the voltage will NOT go higher than say 3.5V or so at the start, that is normal...
As the cell(s) start to fill up you will be able to tweak the voltage, ALWAYS VERIFY the output voltage at the Powersupply Terminals and then at cell terminals, they will show different.
As Cell voltage increases, so will the output voltage on the bench supply.
Once cells reach 3.400 the voltage will start to climb fast (you are at the end of the curve) WATCH CLOSELY by Voltage checking at Cell & PS.
You will have to adjust the Voltage at this point because as the cell fills the supply will increase and it only take a few minutes to go from 3.65V to 3.8 and then 4.0 and it CAN happen quick !
As the cell reaches 3.65 and you dial it in properly so that the output at the PS is 3.65, you will see the amps taken fall down to 2.0A at which point it will really slow as it decreases further, you have reached Saturation at this point.
EAGLE EYES ON IT because it is very easy to run into overcharge.

I started by trying to top 4x280AH OMG it was painful !
I then decided to top each cell independently (much quicker) to 3.65V and drawing <2.0A.
Once all cells were "Topped" then assembled into parallel and Top Balanced at 3.65V till amps drawn fell to 1.7A.
All Cells completely balanced out and settling evenly.
The disconnected parallel to allow cells to "sit" independently, they all settle down at equivalent voltages & IR. After 7 days of "sitting" independently, all cells still match up. 3.438, 3.441, 3.439, 3.440 volts and all at 18mΩ

TIP: After you have fully charged the 1st cell and have the PS dialed to 3.65 (which you can do once the cell is top[ping), LEAVE IT ALONE !
!! Verify that it is at 3.60 to 3.65 at the Powersupply terminals & at the cell terminals with a DMM / DVOM !!
Then just connect the next cell to charge, turn on PS and it will show a Lower Voltage THAT IS OK ! It is looking at target cell voltage and it steps itself down to deal with it, it will do that in CV & CC modes. Just wait, as the cell starts to reach 80% + SOC (over 3.4V) you will see the PS increase the voltage number on the display.
NOTE: The display on the TelkPower may read as 3.7 but output will be 3.65 Always read the Voltage with a DMM at the output terminals on the PS. The dial is very sensitive and the LCD resolution is a tad "soft".

Hope it Helps.
PS, PATIENCE is Important. a single 280AH cell from 2.50 to 3.65 takes about 13 hours with my 15/40 charger.
4 cells in parallel (linked by busbar) will quadruple the time... (Patience Testing)
 
Steve, Danke!
I have 8 280AH coming over in a few weeks. 13 hours each, yikes, I rather have them charge while I am awake, tat would mean 8 days to charge all the cells, hmm.

Could you please tell tell us how the charge current varied,

e.g. - 2 hours @ 20 A > 1 hour @ 15A...
 
You linked to a TP1560 Which is the next up from mine. Mine works well (after I opened it and plugged in a loose connector).
The dials are touchy or finicky. Turn current to full, then dial-up voltage. Note the voltage will NOT go higher than say 3.5V or so at the start, that is normal...
I found the thread about this charger and ordered and it works, 64 batteries are now at 3.53v running continually since last Tuesday. The amperage is now down to around 21amps from a high of 41.

 
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LOL, Freudian Slip ? Contentious Indeed. I can hear the cells yelling at each other "I want More back off, No I want it, U back off..."
Lol I have been contentious with my first two chargers asking whey wont you charge the batteries.
 
I'm on the second charger that does not work, purchased a 40 amp dedicated lifepo4 charger and it does not perform to specs.

I found one similiar mentioned in another thread but the reviews were less than stellar.
I am using the 40 amp version of that power supply. What do you mean when you say the dedicated LiFePO4 charger doesn't perform to specs? Remember that the amps output should drop the closer you get to fully charged.
 
I think you may misunderstand something in relation to charging a cell / pack.
I am using a Tekpower TP1540e so I'll give you the run down.

IF cell is at 2.50-2.75V and I turn on the charger (cell only) it will actually start with 40A CC Constant Current.
By the time the cell reached 3.00-3.10V the Bench PS switches to VC Constant Voltage and Amps drop to 30A +/- a bit and continue to charge at that rate pretty much till the cells reach 3.400 by which time the Amps start to drop "slowly".
When the cells reach 3.60-3.65 (pending where you have the voltage dialed to) the Amps will fall as the cell saturates ultimately ending between 1.5-2.0A drawn.

IF the cell is at 3.20V at start of charge, it WILL NOT Accept 40A, it will start at 30A +/- and proceed as above from there.

This is what I have observed with 280AH cells. I prefer to top charge cells independently then set them in Parallel to Top Balance & finish off the "set" evenly, then allowing them to settle in Parallel for several hours prior to doing any more to them, be it more testing or assembly into a series pack.

Hope it helps, Good Luck.
 
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I do not understand why your power supply doesn't output 40A all the way until your cells reach 3.6v. If you can get 40A out at 2.75v then you have 110W.

Could there be some stray resistance between the power supply and the cells? As an example suppose your cells were 5' away from your power supply and you are using #10 wire. You would then have about 0.01ohms. at 40 amps that would be 0.4v error. That error would cause supply to go into CV mode early.
People forget that copper (no matter what the gauge) is not a superconductor. Steve (like myself) tells the supply what voltage he wants the cell at, thus due to the very low voltage difference, the current flow tapers. When the cell is deeply discharged, you must limit the supply to its rated capacity of 40 amps. You can at any time set your voltage higher and push more current into the cell, but when it is at 3.5 volts and the target voltage for your cell is 3.6, it will take less than 10 minutes to overcharge at 40 amps. No problem with the supply or cell, ohms law explains it all.

If you truly had a superconductor, then certainly pushing 40 amps right up to 3.6 volts without going over is possible. You'd also be very rich.
 
I'm using the copper wire that was sent with the Powersupply. which is 10g I believe, I crimped Ring Terminals onto the wire for connection. There is resistance within, the wires warm up pretty good.
 
I'm using the copper wire that was sent with the Powersupply. which is 10g I believe, I crimped Ring Terminals onto the wire for connection. There is resistance within, the wires warm up pretty good.
You might want to replace that with higher quality wire. If I just use 10 gauge wire with crimped high quality connectors, it is barely above room temperature. My rig with the 50 amp fuse and 45 amp Anderson connectors, the Anderson connector does warm up, but not the wire. Having the fuse just makes me feel better, and the Anderson connector makes it impossible to mix up polarity. Everything is a trade off.
 
Some chargers come with voltage sense cables, I see that it would make sense to use the voltage sense cables.

The voltage drop from the charger post to the battery post will vary with load, I am guessing without sense cables, it would make sense to readjust the voltage when the charge current drops to a lower rate?
 
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