Help with Chargery order

[Tecnodave]

I want to order a Chargery BMS for my LFP cells. I have selected the Chargery BMS 8T as the best fit for my needs. I’m not sure about the high voltage and lo voltage cutoff part of it. Is this included in what I have listed, do I need the DCC-X00 as well? Seems that I do.
the DCC-X00...is this an electronic device or a relay based device

I think I know the answers before I order anything

here is what I will be using it with

2 ea. stacks of 8S 200 amp/hr. LFP cells

MidNite Classic 150 charge controller

Exeltech XP-1100 24 volt inverter OR MagnaSine MS4024AE Inverter, I never use both, normally the smaller


Im assuming that I need the following

1 ea BMS-8T for each cell stack. 2 units for the 2 cell stacks
1 ea DCC-300 or DCC-600,

can anybody with experience with Chargery shed any light on this.....
any suggestions will be considered,


Thanks in advance.

David

 

[snoobler]

You have it.

Recently helped a forum member configure a very similar system, and he's using the same.

The DCC-X00 are what actually cut the circuit to provide the protection. The BMS is just the brain. No current passes through it besides OCV current and balancing current.

Something that's not obvious unless you scour the forum - the DCC have surge protection for capacitor charging ONLY with the manual DCC switch in the OFF position, so make sure they're off when you connect the inverter.

 

[Tecnodave]

snoobler,

Thanks for the verification, So what is the difference between the BMS-8 and the BMS-8T?

my only experience with this type of gear is with a Junsi iCharger i208. This unit is a charger/balancer/ discharged.
It is very similar to some Chargery models but this unit I believe is targeted to model airplane guys with smaller packs than we use in solar......
8S LFP, LILO,LiPo, and ni-cad, nickel-metal hydride, etc, bit different as it is bi-directional, can dump power back to source to test batteries (if source can accept power)

Appleautocorrectmyspelling cannot spell the common abbreviation of nickel metal hydride.....LOL, tried many times
will someone save us from auto spell software.....LOL

 

[snoobler]

BMS8 passes current through itself. 25A limit on charge, 100A limit on discharge.

chargery model power, specially design the equalizer, smart balancer and lipo balancer for R/C model

The iCharger and the BMS have zero correlation conceptually. I have dozens of i206B clones, and the way they work is they actually direct surplus current (typically 0.4A IIRC) to the individual balance wires and use individual cell voltages to modulate total charge/discharge currents. That said, a LiPo balance charger like the one you have can be an extremely useful tool in top balancing the cells.

There are some BMS that can behave as the iCharger, i.e., feed data via the CAN bus and have the SCC modulate its behavior based on individual cells. REC-BMS is one.

The BMS is mostly a traffic cop that just sits there and does nothing UNTIL something goes wrong, and then it closes the DCC. The BMS has the ability to balance the cells with custom operation (all the time, during charge only, above a certain voltage only, etc.). I'm not sure if this particular unit actively balances, i.e., moves current from high voltage cells to low, or if it's passive - activates a resistor to burn off the excess. I think it's the latter.

 

[Tecnodave]

Snoobler,

thanx again. I do use 18650’s and other small cells and I test, charge them with the iCharger, I bought the 208 as it can handle the 24 volt stacks that I am using, it times out with larger cells, I can’t fully charge or discharge banks larger than 20 a.h. Or so. It times out then loses all the data, it also has a monitor mode so I can watch cell voltages when using other sources, it’s been a handy tool

the iCharger is passive balancing, I’ve smoked one, been in there , I blew the fet,s, junsi sold me a refurbished unit, would not take mine back

 

[snoobler]

If your 208 is like my 206s, and I would almost bet my favorite body part on it, you may have a capacity or a time limit set in it that's arbitrarily cutting the operation. Check the settings and disable the capacity and time limits, or set them higher than you expect you need.

Thanks for the correction on the balance method.

 

[Tecnodave]

snoobler,

you are absolutely correct there is a time out timer and a capacity limiter in there and are set too low to do what I was trying to do,....when in dought reread the manual....

there is also another neat trick in there, I have been able to recover cells that were too dead to charge by using the “forming charge” in the ni-cad menu to “wake up” a dead lilo 18650, set it to 2 cells ni-cad , use the “forming charge” but be careful, stop the process when the lilo comes up to 2 volts, reset menu to lithium>lilo>charge

thanks.......it’s all about learning something new...

tecno

 

[snoobler]

I've dug deep into the settings and have 6 programs I use pretty routinely.

I've never used the Forming charge for that (though I use it routinely for NiMH). I've often used plain NiMH at .05A for NCA 18650 rejuvenation efforts; however, your forming charge comment made me re-think it... At 2S on NiMH, you won't exceed 2.96V in the formation charge until it reaches 2.96V and eventually drops to 0.1C for 2.5 hours.

Is there harm in running it up past 2V? I have never worked with Lilo. The NCA 18650 voltages correspond to LiPo values and peak at 4.20V.

 

[Tecnodave]

I’m really skating it, my old experience is FLA , not sure of what im doing in Li, was paid to decommission a bunch of laptops with 486 processors, real bricks that had 9 18650 Panasonic cells, I assumed they were lilo, never really checked, though I sure should have. I have repurposed many into power tools, many that were ni cad or ni mh powered originally, can’t charge with original charger safely, snuck in JST ports to use iCharger , diy ebike , I’m learning. So what program should I be using to charge these, LiLo and LiPo are the only obvious programs, maybe they are others on other chargers. In my documentation from junsi, it is possible to create 10 custom profiles and download them through the USB port

on the forming charge, it will recover cells that normal ni cad or ni mh will not charge , saw somebody “sparking” cells alive on you tube with way too high voltage/current, thought that was dangerous so I improvised

many edits....fighting appleautobutchermyspelling