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I'm a total novice at the top balancing(using a longwei bench top PS), so can't comment with any confidence, but if you charge at 3.4v( @<0.05CA) till the amps go to zero, is the pack not already full at that point? If you then set it to 3.5 and do the same again, is that not in fact...

Only just seen this thread, so haven't read through the 10 previous pages... Could this work (see link below) as it has battery less support...ie connect solar panels to one side and load to other. Gives you a lot of flexibility on both the solar array set ups and also various heating elements...

I wasnt aware of that Craig. I just assumed that with the bench top supplies, those parameters could be accurately applied. Thanks.

????? i'll check back in ten years

@Steve_S Hi steve, just looking for confirmation that you have now used these on the chargery main board input, powered directly from your 24v pos & neg terminals? I assume no mishaps, no complications with mixed grounds and no diodes needed? Thanks.

Ok thanks (y) Only trouble with that, if you only wish to charge to 90% capacity, is it would take much longer with solar at less than 0.1C charge rates. :-(

Is it possible to calculate the DC internal resistance of a cell from the AC impedance data(which weirdly, always seems to be quoted on data sheets!)

Could something like this be adapted? https://www.ebay.com/itm/MG-5000w-48v-230vac-Solar-inverter-max-450V-PV-input-MPPT-solar-charger-80A/273404341882?hash=item3fa82b2e7a:g:d-0AAOSwK3ZbmyR0

Cass, i dont have enough understanding to venture an opinion. I am still trying to figure exactly how each system functions. in 'active balancers', I had thought, that at any point in the discharge(or charge for that matter) cycle, when one cell got out of whack by a certain percentage or mv...

Some interesting ideas among this lot... https://www.pocket-lint.com/gadgets/news/130380-future-batteries-coming-soon-charge-in-seconds-last-months-and-power-over-the-air

Thanks erik. My thinking was, for a final 2P16S (48v300Ah)pack, i would charge each cell to 3.65v individually. Then on achieving this, i would parallel them in groups of two, according to the closest matching voltages. After self equalising, i would connect them into a 16S pack and connect with...

Yes mate, that is what i'm trying to accomplish. The multiplus is an inv/charger. I was hoping i could split the 'charge' relay output on the chargery, with a connection to both the SCC and also to a SSR relay on the incoming grid supply, so that in the event i'm connected to campsite power and...

@JoeHam Thanks Joe, I'm totally inexperienced in electrics....so how would you connect the external power input to the battery pack to provide the required 3A I just assumed you needed the converter to regulate the current to the required 3A???

@Cal Please forgive my stupidity/lack of knowledge, but what does the Com3 port have to do with the seperate dc input socket on the other side of the unit? If the power from the battery pack was run through a SSR (which was itself powered by the LVD relay on the BMS), ie on a low voltage...

I know you are good at designing electronics, but how are you with heat pumps? How about designing a ground source heat pump type system, but one which utilises an evacuated tube array instead of a ground collector, thus giving a much 'higher grade' heat source to start with and potentially a...

I believe it is an M6 screw (xuba 280Ah cells)

Thanks gnubie. I was looking at 3.2v150Ah cells with up to 0.5C charge and 1C discharge with recommended charge voltage of 3.65v however i appreciate what you were saying. Ta

Perhaps something like this listed below, connected between the 24v battery pack and the external power input on the main unit...

Incidentally, when folks say they only charge to 80-90% capacity, how do they do it if they ignore voltage references?

@FilterGuy Thanks for giving me so much of your time/experience tonight....much appreciated.

Great info Jason, However the storage conditions for my particular cells datasheet suggests that 6 months storage is ok, and that the battery pack should be charged and discharged, but not necessarily from 100% to 0%(many folks just run their cells from 80% to 20% SOC permanently, for longevity...

@Steve_S Steve, another question on the chargery set up if you dont mind(well more specifically on the use of deltec shunt). I noted in the Chargery 16T spec sheet that the 'suggested' shunt should be equal/less than 75mv. Any idea the reason for this? I like the idea of the deltec, but wondered...

Yes, i had thought of doing a three step charge to 3.4, then 3.5 then 3.65, but at the amps being put in, i was told by another poster that the pack would be overcharged long before getting to 3.65v On a 280ah cell, you need to be putting in over 14A so that you can see the current tail off...

So they have discontinued the BMS16 :-( Was looking at using an independant active balancer and was hoping to avoid any possible interference between the 1.2A passive balancing of the T model and the active balancer.....hope that is still possible.

Would something like this do? https://www.aliexpress.com/item/32847476915.html?spm=a2g0o.detail.1000014.9.67d1367az0OXqa&gps-id=pcDetailBottomMoreOtherSeller&scm=1007.13338.128125.0&scm_id=1007.13338.128125.0&scm-url=1007.13338.128125.0&pvid=f7d9d32a-37d0-4f35-868f-db8afb37b785

Just checking with all you corrosion whizzes... I'm changing from the screws/busbars supplied by Xuba for my 280's to aluminium flanged studs. Busbars are going to be braided copper with tinned copper lugs. Any benefit to using zinc nyloc nuts, so that the corrosion between the nut and the...

Are there any serious problems in simply using a very high efficiency house fridge in a RV? An A+++ rated fridge running off the inverter looks like it would have a low annual kwh consumption. What are the likely problems going this route versus a compressor fridge at several times the cost for...

welcome on board :)

Thanks steve. I've been trying to find one of Will videos, where he is seen, charging up the caps with a resistor. If i find that, then i'm sure i can work it out from there. I really just depends what amperage is needed, to achieve the charging of the caps over the time allowed. I will keep...

Thanks.....just that one of the 'cells' specification sheet i was looking at had an AC impedance of only 0.25milliohms, which seemed far removed from your previous example of 5 milliohms...thought there might be a massive difference between the two. Much appreciate all the assistance you have...

Had they all been sold as 272's you would be delighted. As 280's, there are a fairly high number below 98% capacity. I'll be interested to see your final tally. How much have you varied the C rates?

Could you 'site' the battery bank inside an old 'non functional' chest freezer, with input and output computer fans built into the lid/floor etc, which get relay activated on climbing above say 30degC ambient temp. If i recall correctly, i think the lifepo4 batteries get the most cycles at a...

I dont want to lose all the configuration settings, since i will not be taking the pack to 100% or 0% soc thereafter. I cant get the version 4.03 update which i believe you need to maintain the settings(from a previous post)

Questions... 1/Looking at the above setup, any reason why i couldn't use thick copper plates to simultaneously make the 2P & Series connections? 2/Understanding that heat rises, if i insulate around each cell with kingspan 25mm, this provides rigidity within the confines of a casement, plus...

Must be quite a few having their HVD triggered well early. Great job highlighting this issue by the way.

Hmmm, thats a significant percentage difference on that 4th spring. I suppose you will eventually glean more info on repeatability, but i'm certainly curious why that one was different!

It was my own idea, to solve my main worry, of going into the cell, but it took some time to source someone to machine exactly what i wanted. Then after i had used then...i would modify if doing the same again.....put a hex on the flange, make it 5mm thick to get a key onto it and i would seal...

Fantsastic idea. Great job on these video's. (y)

No, you cannot torque to higher than 4Nm, or else the stress goes on the underlying 6mm threads below the flange and above 8Nm, i sheared the stud. I would definately increase the size of the flange area. Edit....a stronger version of aluminium might help of course....but i just find everything...

Unless i have misread steves post above which said "non T ones are different but now discontinued too", i just assumed he was correct.

Most of the EE's or related on here will already have all the equipment necessary to check all the parameters, but Will's video's tempt the RV guys who bought their vehicle with an AGM/FLA system but who now see the benefits of Lithium and spike their interest. Against this, is the cost of both...

@UK Energy Hub Hi Tim, does UK Energy Hub have 'sales' or 'free delivery' from time to time....just worth me keeping in mind as a potential UK purchaser. I have saved a link to your website in any case. Thanks

Yes i understand your reasoning, but surely after you redo the settings and then only charge to 80% soc, your readings will be all wrong, or do you charge once more to 100% SOC? If i run my battery pack power to the external power source input, through a SSR connected to the discharge relay...

@Supervstech So, in the case of a 2P16S setup, where cells are paralleled first, could you hook up 2 BMS's(one down either side of the pack) such that you get back to a faster 'reaction time' to the imbalance. Would one BMS, fight with the other, since they would both measure each twin...

@tictag Hi tictag, on the back of your comments, that higher voltages are better for MPPT, if my 'all in one system' is max rated at 145V but the MPPT in the unit is rated at 60 - 115V, what happens if the series connected panels equal say 130 ocv. Does the MPPT simply ignore the voltage from...

Think that links to the BMS16T though Try...

Many thanks for those screenshots....so it looks like yours is different to mine, since my min default is 2v on a 24v system. :cry: It seems back to front....you have a min of 1v on a 48v sys, i'm 2v on a 24v sys....so you have 4x more accuracy in setting!!! Hmmm... i wonder if its because i'm...

So on a single cell that is sitting at 2.5v, with a charging voltage of 4v, =4-2.5 =1.5/ 0.00025 =6000A When the cell approaches cut off point at 3.6v = 4-3.6 = 0.4/0.00025=1600A in theory? Even if you allow double for the DC internal resistance, it still shouldn't influence the charging if my...

Im looking at a standard home A+++ fridge (of 147 litres capacity) for use in my coach to camper van conversion. The annual power consumption is 62kWh/annum Would'nt appear to be a big draw on my 3000W inverter. It would only be getting used during summer months....so no unheated room use. Is a...

Dont sweat it steve....you have put many onto the chargery units...you should be on a commission....lol