Battery Hookup new listing “Case 100x 3.3v 2200mah - 200x 18650 Lifepo4” for $100.00 + shipping

[sam_sam_sam]

That's not very promising that it can't take 1C charge..and only can discharge at C/3 ?

I could have put the load higher but the reason I did not do this right now is that I want the battery pack to be discharged evenly so that I can determine at what current can I charge them at an still be in the good range plus I was setting up the adjustable switching power supply for the charging test portion but it appears that the battery was almost fully charged because the charge curve was very steep and voltages were all over the place which is typical of a battery pack nearly fully charged and dose not have a balancing function on the BMS protection board

According to the description from Battery Hookup the maximum discharge current is 15 amps which I will run this tomorrow sometime after I run the charging test

I will be happy if I get very close to 6 amp hours out of this battery pack seeing how these battery packs were made in 2021 nearly 4 years old now for the price of them

Remember these are sold as used not new they say that they are slightly used let see if this is the case or not

What I am not happy with this is the voltages all over the place this got me a little concerned about why is this the case because even with out a balancing BMS function it should be better than this I would think

[eccerr0r]

Theoretically the drop of charge and discharge should be pretty much the same, assuming no active balancing which I don't expect. This looks like passive balancing, and would need to do so if the interstitials aren't ported out...

[sam_sam_sam]

Theoretically the drop of charge and discharge should be pretty much the same, assuming no active balancing which I don't expect. This looks like passive balancing, and would need to do so if the interstitials aren't ported out...

Or just put another set of BMS protection wires and used them on a balancing board which I could do I did not think about doing that but that is an option that I could do because I actually bought one a while back that I actually modified so that I could hook up the BMS protection board to hook it up to use this way when the BMS protection boards did not come with this option

Below is a picture of the discharging curve and it looks very good on a two amp load and it is almost half of it rated capacity for amp hours

The reason for setting the discharge cutoff voltage at 16 volts I want to see at what voltage does the BMS protection board cutoff at is it very low and I need to be concerned about depending on the device I am using it on

Dose really cutoff at 20 volts as they claim in the battery hookup description or is it really a lot lower than this

Because the voltage got to 3.8 volts per cell of course not all of them reach this voltage I stopped the testing when I saw this high have manually adjust the voltage and current in the charging function on this battery testing machine it not like the other battery testing machines that I have that adjust it for you if you put the right parameters in correctly

I am giving some real thought about buying a decayed Lipo 4 charger that can go up to 80 volts at 15 amps and both are adjustable but unfortunately it is a little bit pricey unfortunately but supposedly it has better controls of the current we will see if I decide to buy one or not

I have a 80 volt 2.5 amp version but unfortunately the current adjustment is a little too fast for my liking and the lower end of the adjustment I would prefer that it took at one complete turn and then slowly go up in milliamperes instead really quick and you are over one amp you have to turn very slowly to dial in the amount of current you want

[eccerr0r]

But wouldn't that mean you have to take the pack apart to access the interstitials? You can't connect the bms protection wires without opening it, and it must be able to balance as-is else that's a recipe for leaking magic smoke...?

[sam_sam_sam]

But wouldn't that mean you have to take the pack apart to access the interstitials? You can't connect the bms protection wires without opening it, and it must be able to balance as-is else that's a recipe for leaking magic smoke...?

Yes it would require you to remove the packaging material away from the top and bottom but this pack is put together pretty good and it was fairly easy and simple to add the individual battery voltage leads to the tabbing that is already there for the BMS voltage leads which I was very surprised how easily it for me to be able to do it it has plastic plates all round the battery cells and foam around the outside of the battery cells there is a plastic plate unde the BMS protection board and there enough tabbing that you could attach another heavy gauge wire to it as well if you want to

For me separating the battery pack in two separate battery banks is going to be a challenge because they glued the battery cells together and unless I can take a box cutter to separate them that I might have to come up with a better plan

I think this is the first time that I have had 32700 battery before that were good enough to do something with

I have had a bunch of 26700 before and had the issue with the heat shrink tubing that was used extremely thin wow that gave me a scare when it shorted out so easily because of how thin it was I have not done anything with the rest of that pack yet because of it

[eccerr0r]

interesting... going to be annoying to reconfigure then... but still, balancing needed to be done somewhere or were these packs never intended to be balanced -- which is hard to believe.

[sam_sam_sam]

interesting... going to be annoying to reconfigure then... but still, balancing needed to be done somewhere or were these packs never intended to be balanced -- which is hard to believe.

I found a solution to this issue with it charging back up with out it being way out of wack you have to start off by charging it very very slowly I could not believe that this made a big difference in the way the charging curve looked like once all the battery voltages were above 3.24 volts the difference at 3.50 volts was 0.010 volts still in the good range which the maximum value and still be in the good range 0.024 volts

So what I did was turn back down the charging current to 0.100 amps and going to leave it over night this way I can get it back into balance again and run the discharge rate at 15 amps and then try to fast charging again but my maximum charge rate at the moment is 2.5 amps at 26 volts because I do have any switching power supplies that voltage and current adjustable higher than maybe the 48 volt one if I remember where it is now
As you can see in the last picture that the charging voltage actually came down a little from where it stared from which is interesting because I have not seen this before either maybe this BMS has bottom balancing and not a top one because I found it interesting that when I lowered the charging current way down and waited for a little I noticed that the differential voltage was slowly dropping down I thought to myself just how low will this differential become so I just sat there and waited and to my surprise it came down to about 0.007 which when I saw this I wondered what would happen if now I slowly increased the current would it go way out of wack again to my surprise it did not yes the differential had climbed back up to 0.014 but it was still very stable and the voltages were not climbing back up very quickly at this point but I was getting tired and wanting to call it night and get some sleep

The charging curve is a little bit steeper than I like to see it at this current level but it is a lot better than what it started out looking like when it was finished doing the discharge load test it was so steep that I thought there was something wrong with these battery cells because the discharge load testing revealed that 95% capacity was still left this was not making very much sense to me and this was the case I have never seen this before there has to be a reason for why this charging curve looks like real bad shit

If you look at the last picture you will see the amount of milliamperes hours this battery pack has and it was not completely charged up to where the BMS turned off the output current to stop the charging cycle and I did not let it finish discharging because it already started rolling off to where it was going turn off I just did not take a picture of it but the battery cell voltage was around 2.5 volts or so the cutoff voltage was a little bit lower than 20 volts not real bad but not necessarily real good either so let see what the charging cutoff voltage is and is it reasonable or not and is it something to be concerned about or not

This looked worse than the battery cells that were Panasonic from China for my heat shrink label making machine and they were really bad looking

It is going to be very difficult to do this type of balancing unless you have some way to monitor all of the individual battery cells and wait for the battery differential to become very small then turn up the current to fast charging them something like this makes it very easy to do there are two versions of this individual battery voltage monitoring module one has the one size connector this version has both the small pins and smaller pin spacing the other version has the more pin spacing and the pins are narrower in this version yes the unit is a little pricey but to me it is worth it because you can see it in real time with the battery testing machine graphics cart and looking at them at about the same time

https://www.ebay.com/itm/15509052993...HP8G44XM2GKK9S



More testing tomorrow sometime in the afternoon probably or maybe little bit earlier than this we will see what happens in the morning

[eccerr0r]

Well at least that's 5Ah. hmm.

I wonder if it really can take 15A... though I guess it depends on the kind of mosfets that are being used, and the cell health of course...

[sam_sam_sam]

Well at least that's 5Ah. hmm.

I wonder if it really can take 15A... though I guess it depends on the kind of mosfets that are being used, and the cell health of course...

I will know just how much current you can pull from them and the discharge load curve still looks decent

How I will do this is to start at 2 amp load and keep increasing it by one amp until the stepping ladder effect is no longer there and this will tell me just how much current you can actually pull from these battery cells with out it just becoming to step with a very straight line which is not going give any good results

Battery hookup claims that they can handle 15 amps so lets just see if this is the case yes I am torcher testing the hell out of this battery pack and it's BMS protection board but I need to know if it can handle the stress of my testing in the past I have found some BMS protection boards are real crap and could not handle the stress test that I gave them but I knew just how far I could push the BMS protection boards by doing this type of testing yes I try to make them fail my type of testing

Yes you are partially correct that if it is actually capable doing that amount load and the data sheet says that it should and it does not then we have a serious problem with how much they may have degraded they have become but usually it also effects the milliamperes hours as well and that would be if you had only 50% of its rated capacity you would expect this but not if you are at 95% of capacity still left this is another story

Now the more current load you have the less milliamperes you will get but it should not drastically reduce if it is then it might be showing it age to a certain extent

[eccerr0r]

Since you have it open can you read the parts used for the mosfets? I'm wondering if I do end up modding for 12V I'll need to add some more mosfets. 15A would mean I don't have to but would be nice to discharge at 1C... meaning now 12A at 12V.

Oh an *#@(#**%#@#!#. I have a 2A wall plug that was oddly enough 29.2 volts. I modded it to 25.2 volts... I wonder if I need to mod back though I'll have a need to use both voltages...

Then again this 24V PSU I just fixed I probably could somehow hack in some CC/CV support, and technically it probably would be a little more efficient with higher voltages (though at low voltage/fully discharged it will just be as inefficient as any other linear PSU...)

[sam_sam_sam]

I will try to see if I can read the numbers on the mosfets and also post a picture of it right now there is a paper label that is on top of all of them now If you are able to modify this BMS protection board would you mind sharing your results and how you did it I would really appreciate it seeing how you did it

I have a bunch of 5 volt at 50 amp Meanwell switching power supplies that I could send you a couple of them just pay for the shipping I have fix several of them but I have not tried to rewind a switching power supply to a higher voltage and somewhat lower current I have watched several YouTube videos on the subject but never tried it before I only repaired them before

I bought them from a eBay seller that was selling them for parts he still has a bunch of them but these do not run at all the ones that I bought have running issues or will turn on but not at the correct voltage or very little current and shut off if you are interested in the eBay seller I can post website link to it

The biggest issue with these switching power supplies is that they were used in LED displays signs and need to be cleaned cooling fans do not necessarily run correctly if they run at all and all of the capacitors need to be replaced especially the low value UF ones and one of them so far the main filtering capacitors one of them was completely open and top was swollen and one of them there was a couple film capacitors that were cracked and not good

As far as the power supply that you modify how easy would it be to put a switch to change back and forth between the two voltages just a thought

There is a correction about my 80 volt switching power supply it actually goes up to 3.5 amps output not the 2.5 amps that I stated earlier

The charging curve looks very good at 3.5 amp charging rate its voltage fluctuations are less than 0.017 the last time I looked it very possible that they sat in storage for a while while and self discharged a little bit to get them out of balance but it appears that the BMS balancing protection board was able to correct this situation when the charging current is turned down to 500 milliamperes for a while until all battery cells get to a certain voltage level and become balanced and then you can fast charge them to your harts content

It is also possible that these battery cells were not matched correctly to begin with and the amp hours are not very close to being with when each battery cell goes into voltage roll of situation which will throw of the balance of them which is why I do not like the cutoff voltage for discharging and charging cutoff voltage are not very realistic the way they are done but it is what it is and unless you know how to modify the voltage parameters you basically have to live with it if do not go through the trouble of modifying them

My suspicious about the battery pack and why they were replaced is because the devices that they are in must have some monitoring system that when it see a drastically steep voltage curve it is time to replace the battery packs the running would be somewhat lower but this does not mean that they are bad it just means that the device that it was in has detriment that it's performance has fell below allowable limits

Here is my biggest question and concerns about what I am seeing with the testing that I have done so far this do I just use them the way they are not match by milliamperes anymore and rematch them again as close as possible for the BMS balancing protection board to function properly and live with the unbalance factor and a little bit shorter running time or do I go down the rabbit hole and rebalance them so the BMS balancing function works better

This BMS balancing board is typical of Lipo 4 that the voltage cutoff is 3.8something before it stops the charging cycle and at 2.50 on the discharge cycle ( to me it would make more sense if it was when the voltage starts rolling off for the charging and discharge cycles that the charging and discharging cycles are terminated instead of doing it way manufacturers seem to want to the other way because the little bit more milliamperes is not much use in the first place anyway)

I will have to prepare another battery pack for testing later on today that about all the time I will have today but this should give you an idea about weather or not to buy these battery packs or not

I hope this helps you decide what to do

[sam_sam_sam]

Here is the website listing for this battery pack at Battery Hookup

https://batteryhookup.com/collection...y-with-bms-24v

Here are the final results of the 10 amp load test on this battery pack from Battery Hookup for $9.99 per pack to me well worth the price of it for the results that I see
When the voltage starts to rolls off the battery pack is when you see the difference between battery cells becomes the greatest and you can see this in individual battery voltage monitoring meter module screen

One important note the battery pack does get warm to touch and the mosfets do get a little bit warm as well nothing to be concerned about but if load testing them at 15 amp load might be a hole difference story altogether

For my purposes I have no plans to test it to there limitations because I not after torcher testing used battery pack to this extent I very happy that it can do 10 amp load for 30 minutes above 24.00 volts but it does not last much longer than this—> this is not an issue


I am very pleased with the results that I see from this battery pack I going to prepare another one for testing later on today for now I going to be cooking on my pellet grill so be gone for a while today doing this

But I am going to approach this testing a little bit differently when I first put it on the battery testing machine I going set the charging rate for 500 milliamperes to start off with until the battery cells become balanced again then turn up the charging rate to 3.5 amps and see how well this strategy works for this BMS balancing protection board

Then load test it at two amps then recharge it to see how balanced the battery pack is and then run the load test again and do it at 10 amps this time and then let it sit for several hours and see how well it recovers voltage wise

[sam_sam_sam]

Since you have it open can you read the parts used for the mosfets? I'm wondering if I do end up modding for 12V I'll need to add some more mosfets. 15A would mean I don't have to but would be nice to discharge at 1C... meaning now 12A at 12 volts

If you decide to buy some and do what you are talking about doing can you please share what you did so I can do the same thing to one of mine to make a 12 volt battery pack with these battery cells and use this format because I think about doing something along those lines or instead two rows just doing one longer row instead of how it is now

I have an idea of how you could do it but not sure if would work on this board because of the way it is setup and I not sure if I want to scarify one for experimentation at this point I might consider it later when I have decided how many battery packs that I need for my battery backups and maybe another project that I have think about doing but how I going to go about it I am not sure of at this point in time

What I can read is Qunvos from what I can make out by tilting a little bit to one side this line is hard to read clearly

What I can read is 30BY5 the second line this is very clearly read with out any problems

One note after sometime has elapsed the battery voltages are as follows
#1. 3.028
#2. 2.967
#3. 2.946
#4. 2.984
#5. 2.839
#6. 3.010
#7. 3.022
#8. 2.889

With a differential of 0.188 and is in maintenance of the battery pack is need

I am very slowly charging this battery pack up to where it is balanced again and put it in storage for a little while

While I test some more battery packs before I decide on what plan of action to take about configuring the battery packs into the battery backup or do I have to remove one battery cell for the battery backup to charge the battery pack up completely

I am going to run a couple of tests with the way they are now and see how well it performs in this application and will post the results as I get them

[eccerr0r]

6 x 60N06? hmm...

[sam_sam_sam]

6 x 60N06? hmm...

Now how did you determine this from what I posted what lookup table are you using for this

If this is the correct part number that you have could you put them in series and get 48 volts without damaging the mosfets just curious about this because Battery Hookup does not recommend doing this are they correct about this

[eccerr0r]

your picture has a cut off picture of the MOSFETs? Trying to extrapolate the cut off portion of the photograph... but if it's really 60N06 something doesn't seem quite right... or maybe it is...

[sam_sam_sam]

your picture has a cut off picture of the MOSFETs? Trying to extrapolate the cut off portion of the photograph... but if it's really 60N06 something doesn't seem quite right... or maybe it is...

Because of the height of the battery pack it is difficult to get the camera to work properly and at the angle I had to have it to get a decent picture of it that why I wrote what I could make out clearly and what I could not make out real clearly to make it easier to make out what you could see

I still want to know how you came up 60N06 because what you can clearly make out is 30BY5

I am unable to find any information about the markings on this ic chip part number so who knows what the part number it really is

[eccerr0r]

Because 30BY5 looks like a vacuum tube part number :p
60N06 above the 30BY5 is a reasonable part number based on the photograph, unless that was meant to be something else..

60N06 has reasonable specs for a prot mosfet... though might not be enough for reconfigure for lower volts and more amps.

[sam_sam_sam]

Here is a BMS protection boards that this 30 amps at 12 volts for the regulator 4.2 volt version I really only the balancing version most of the time unless I do not use decent battery cells then a regular BMS protection boards will do the job

https://www.ebay.com/itm/39627059169...Bk9SR_aAhs7KZQ

Here is the lipo4 BMS balancing protection board with a single ic chip for the individual battery cell voltage controller which I will probably or a couple of them to test if they really cutoff at 3.65 volts according to the description that the seller is giving it

https://www.ebay.com/itm/40466954791...Bk9SR7zqns_KZQ

For around $5.50 shipping is free but it is coming from China so it will take about a month to get here

[eccerr0r]

Going to try hard not to have to buy more stuff, but batteries I cannot make out of resistors and capacitors. I have some 75N06's that I could use, technically I could just outright replace them and get a bit better performance.