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Batteries exposure is not the only concern to me on the first picture. You can clearly see a red wire without protection chaffing against the frame...which is connected to ground. As it does not seem there is any fuse after the battery, it is a problem to come!

He can also discharge this single cell to the same level than the other with a load applied only on this cell. This will speed up the process. Balancing at 30 mA is really for minimum adjustement on a well balance pack... This is the drawback of LFP cells, the voltage does not gives a good...

Thanks Travis! This is an option I will consider at a later stage as finally, over the 14 batteries I have, 1 is dead (one cell at zero with leaking cells...), 6 were recovered from 2,8V to fully charge and give average 139 Ah while being discharge at C/10, and the seven others seems to work as...

Well it was an issue with the RS 485 dongle...After replacing it, I have been able to read and save current configuration.

I agree, an active BMS would transfer from one cell to an other but: -average would still be 100 A (if 100A are drawn from the whole pack) -in no case the 100A would be divided by the number of cells. This is in my opinion the minimum basics one should know before "toying" with such huge cell...

Do you start the software in admin mode?

Each cell share the total power to be provided. Power is the result of voltage multiplied by Current. In série, current is constant and voltage is spread over all cells, in parallel, voltage is constant and current is spread between all cells. So the total power is always shared between all...

I'm using enphase M215 micro inverters with 6 Valence U27-12XP batteries (2S-3P) and the inverter are connecting and produce max possible power without any problem. The current is automatically adjusted to match the decreasing voltage. I use this to store excess daily production and use it to...

You need to charge each battery individually up to 14.6V, in order to properly balance each cell and reset the SOC. I'm in this exercise with some batteries sitting for a few months and which need to be properly balanced before being connected in parallel. You could also connect all batteries...

Something is not matching. LFP is 3.65V max, and 4.18/4.2 is lithium ion chemistery. I would be very cautious when doing such a loop, it may happen the inverter is not isolated such as transformerless solar inverter. Regarding the unbalance of your pack, there is definitely a problem with the...

Couldn't it be the BMS that switch off the output? In any case, I would not accept a 0V battery as it is clearly advertised the battery is tested before shipping...

13.6V is definitely not a sign the battery is fully charged and balanced. Full charge is 14.6, i.e all cells at 3.65V. Having 0 Amps at 13.6 may be with a low cell, that will trigger the low voltage protection of the BMS.

If possible, I would use 2 relays: -one to disconnect charging on cell high voltage, more likely to happen at low charging current because end of charge -one to disconnect load on cell low voltage, which will keep charging ability to restore asap battery capacity... I just look at the VC1...

Hi! Have you try any other adaptors, such as this one...

This power supply will work only if limit current to 40A, and not go in some sort of security mode. Charging the cells will be seen for the power supply as a short circuit on its output, and you need to check how it will handle this.

Maybe a little bit more details on the batteries and BMS? it maybe the BMS which is triggering a high current protection. 1500W over 12V battery bank is above 100Amps... Any bad connection would also trigger a low voltage at inverter input under load.

If you don't want to provide the required details, then there is no way to help you...

The pictures of the connections are horrible. It is even dangerous, as it could lead to overheating and starting a fire! It is poor design, poor assembly and absolutely 0 quality control! I would open all batteries and rebuilt these batteries with proper washer on both sides of the PCB, to be...

Your controller is lacking a remote switch...Switching off the panel will still let the alternator to take over charging. An option maybe is to simulate an overvoltage through the battery voltage sensor or an overtemp through the temperature sensor. Then also, this relay should be a safety...

An update on my situation! I have received the second car and batteries were all showing above 13.2 volts! But previous Owner has mixed batteries of the 2 car to rebuilt a pack, but just forgetting to get them balanced before connected in serie! No need to say the BMS was cutting the charge as...

Maybe one good thing anyway...Imagine you installed the pack in your golf cart and use it with this bad connection? You may have ended with a toasted battery and a burnt golf cart...

Be careful, internal BMS of each battery does not prevent anything, unless it is connected to a Valence BMS properly setup. Internal BMS only provide light balancing of the internal cells if connected to an an RS485 device. If not plugged, the internal BMS do nothing... There is no FET or relay...

I don't follow you on the 2A/cell...Amp are constant over a serial connection. So if you have 16 cells in serie to achieve a 48V pack, and this pack is delivering 140A, then each cell is delivering 140A also... If you have 4 48V pack in parallel, then, each pack deliver 35A, but each individuel...

I was calculating the amp following the 1800W asked by Corbury. 1800W at 12V gives 150A but if you consider battery is more around 13.4 rather than 12V, it lower the AMP around 134A. Having 2 in parallel will gives a C/2 charge on the battery which is no problem.

Not exactly...as the positive of a cell is the negative of the next one... The wires are connected like this: -negative of battery which is also negative of cell 1 -positive cell 1which is also negative cell 2 -positive cell2 which is also negative cell 3 -positive cell 3which is also negative...

I had one battery like this once. It took ages for the balance to bring back all cell at the same level...I would activate a small load just to bring back the highest cell at 3.65V maximum, and then leave the battery alone just to see if all the cells converge. The main issue is that 2 cells...

Sounds normal to me...

I would use CC/CV, with a limit at 13,8V at least. But first, you have to be sure that internal cells are balanced. So connect to the battery and check the cells individual voltage. 13.02V is on the low side, you can't be sure the battery is charged.

10A at 30V? It exceed the capacity of the tester...I bet the MOSFET will go in flame and smoke!

This is not a top balance...You should connect all cells in parallel and charge the pack to 3.65V all together. Once current drops below a certain amount, this means your cells are balanced... You could have all cells at the same voltage, but with still current flowing from one to the other...

I think you mean in parallel? Else, you will end with a 96V battery... In serie, it is a no go, in parallel, it could be possible, even if not recommended.

2 Valence, connected in parallel, are perfectly able to sustain a 150A load, which is 75A per battery...Unless your batteries are completely toasted, which is still an option.

That's a huge number of cells! Testing them one by one will be tricky! I would simply charge them up to 3.65V and connect them 16 by 16 to built a 48V battery, with a BMS. Then running a load like an inverter, I would check if there is any runner on the pack and replace it. It all depends what...

jump directly to a 16S pack...it will be quicker to highlight runners and bad cells...You maybe very surprised that none of cells will have been damaged...If none of them was at 0V, I would bet they are all in good condition!

If you don't mind voiding warranty, you can open the cover and remove Valence BMS borad. You have a plug with 5 wores connected to each cell. You can easily connect any BMS you want!

The 3 mV spread does not mean a lot depending of the SOC...You have to charge each battery up to 3,65V/cell to check if cells are really balanced.

Nice software! I already have a setup in my car, with a LV BMS and seven U27-12XP battery. The Valence Config and Monitoring software is not the best looking software and I would love to get it replaced by a software like yours. I have already all harwarde needed, including the CANUSB adapter...

Not the same, but definitely a very hot point in your pack. Depending on the surroundings, it could lead to a fire. Most probable scenario is that you would have had such resistance that the overall voltage of the pack would have fall below LVD, or you would have had a low cell voltage under...

Hi! I may have in a near future 2 setup of 7 batteries together with a Valence BMS LV for each of them. This setup are used in electrical cars. I know they are sitting in a hangar for almost 3 years without a single charge, and I'm afraid batteries will be overdischarged... Anyway, for the time...

It may be that the cells are 75Ah...The Chinese seller are good in cumultaing both voltage and capacity in the description... DO you have a mean to open the battery? It would be good to check the cell inside. Definitely, a 300Ah cell is around 5.5 kg, so the spec are very light... Also comments...

That's great! Battery seems to be in very good condition with only 7 cycles and no reset, which means no undervoltage! I whish I could find such an opportunity to replace my dead batteries!

Thanks for your feedback, which give me hope for at least 6 batteries. It seems they are charging normally with very low spread over the cells, even without active balancing. Theses batteries have pushed "only" 77 kWh each, so more or less 45 cycles... Unfortunately, as said in my first...

I feel your pain! I have also one battery exhibiting the same behaviour...cell 2 on mine is dead also... that's funny it is the same cell Maybe we could rebuilt one battery with our 2 dead! ;-)

I'm sorry, I think there is a misunderstanding here...In Serie, all cells are pushing the same Amp amount. Voltage maybe different. But definitely, if battery is outputting 140A, then all cells are outputting 140A. But as there internal resistance may vary, the total voltage is the sum of all...

Ok, I will try to answer as far as I can, as I don't know your equipment, just trying to put some logics in my comments! I assume you have all 4 batteries connected in parallel to achieve a 12V/552 Ah battery bank, right? Also, are you able to get a device plugged in the RS 485 network of the 4...

I will follow your thread as this format together with the high C rate is exciting. I was considering 32700 format to rebuild a electrical vehicle battery pack, especially the ones with threaded connection, but this format seems to be more efficient. What kind of busbar do you anticipate, and...

I had to test 2 adapters before finding one which work... The one ordered from Aliexpress https://fr.aliexpress.com/item/33025022759.html?spm=a2g0s.9042311.0.0.27426c37UYzDiT was not working...

You will have to monitor very closely the voltage adjustment to stay at the 40A limit...

No answer to the questions, no way to help you...What is your battery brand? BMS? Charger? Inverter? picture of the connections? Also, 14.6 volts for a LFP battery is full charge at 3.65V per cell. So if your inverter stops under load with a battery at such voltage, that means you are exceeding...

Hi! I'm looking for some cells dealer having stock in EU and with good reputation. Do you have any contact to share? Thanks in advance!