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Experiences or opinions on the Chargery BMS?

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In my search for a decent BMS for a lifepo4 battery bank, I've come across the Chargery BMS8T (they make 8s, 16s, and 24s models). Here is a link to the documentation (PDF).

I'm wondering if anyone has any experience with this BMS or has looked into it?

It looks like a good product, but I'm really not informed enough about battery management to trust my own opinion. What I like about it is that it has high charge current (up to 600A using external relays for charge and discharge protection), and a balancing current of 1.2A. I don't need anywhere near that current, but would like to be able to handle at least 60A charge current reliably. It has an external lcd screen, and is pretty customizable.

I'd love to hear your opinion of the BMS if you have any experience with it or have looked into it.
 
I went through the BMS Hunt and chose the Chargery BMS8T for my LFP Pack, because of how it's made and what it does, my runner up was the TinyBMS. I did not just "pick it out of the hat" either, as a local Solar Builder here (who I know quite well) uses them with various battery packs which he builds out of EV Packs, such as those from Chevy Volt's. I also must say that Jason Wang @ Chargery is excellent at answering questions and helping out with any issues you may have... I bought directly from Chargery, including the relays (these are serious duty relays too BTW) and the delay board as well (strongly suggested).

* On the amperage. The rating Is for output on the battery side and the maximum loads It can handle, so 60A outbound isn't much at all.... I'm running 24v and can see 100A out of the battery bank by turning on 2 LED lights, the coffee maker (run 7 minutes and uses the thermal carafe so no warmer plate) and having the radiant heating running (only uses 2amps) If the deep well (260') water pump kicks on (120v soft start) It will ramp from 500W to 1000W when at full pressure cutoff point can tip it up to 150A @ the battery. Also you have to take into account the Maximum Watts your inverter can put out on a surge and the relays should handle that. The delay board helps to set an allowed surge delay, otherwise it can trip the BMS and shut down the pack, surge is usually no more that 2 sec but the board can be configured from 2,3 or 6 seconds

I am disassembling & redoing my ShunBin LFP pack this weekend which will have the Chargery, new 1/4"x1.5" solid copper busbars (made from 110 Copper bar stock). There are links in my Signature to the LPF an the BMS as well... I will post photo's later this weekend or on Monday on this part of the project.
 
I went through the BMS Hunt and chose the Chargery BMS8T for my LFP Pack, because of how it's made and what it does, my runner up was the TinyBMS.

I just checked out TinyBMS, it looks like a good option. What tipped the scales for you in choosing the Chargery over the TinyBMS?

I also must say that Jason Wang @ Chargery is excellent at answering questions and helping out with any issues you may have... I bought directly from Chargery, including the relays (these are serious duty relays too BTW) and the delay board as well (strongly suggested).

This is good to hear. I feel like one of the biggest problems with many of the BMS options out there is that there is little to no support or accurate technical details, or where support is available there is a big language barrier.

* On the amperage. The rating Is for output on the battery side and the maximum loads It can handle, so 60A outbound isn't much at all.... Also you have to take into account the Maximum Watts your inverter can put out on a surge and the relays should handle that. The delay board helps to set an allowed surge delay, otherwise it can trip the BMS and shut down the pack, surge is usually no more that 2 sec but the board can be configured from 2,3 or 6 seconds

When I referred to needing 60A, I was referring to input (from my solar array and/or vehicle alternator). My output requirements would be higher 2-3kw (4-6kw peak) inverter @ 24v (so something like 300 amps would probably be more than safe)

Thanks for the feedback/advice, I will have to take a closer look at your design/build posts.
 
Chargery has options up to 600 amps the unit only reads battery voltages and does some balancing so there are no issues incoming or outgoing with high amp rates.

This is probably a dumb (or poorly framed) question. But is the Chargery BMS a 'full BMS'? In other words are any safety or monitoring features lost by outsourcing charge and discharge disconnects to external relays?
 
I've got BMS16T, mainly because it using external relays for the safety shutoffs is so much better because you can tailor the size of the relay to the size of the load AND replace them if/when they go bad. I also like the external shunt too.

Finally, I love the remote panel - I've run a phone cable from the battery area all the way up to my office so I can keep an eye on the bank from up here without having to turn on a PC or find my phone and I can hear any alert it puts out. I've only played around with mine with cells I have laying around in the basement shop for now until I get the new bank put together but so far my impression is "damn, this is a nice gadget". Graphics and menu could be a little better though.

And yes it's a full bms and can do 1.2(ish) amps of balance current.
 
I have a BMS8T on the way. I like it's adjustability. I like not having mosfets for load control, especially at the higher amps. In short , the features and pricing are what sold me. And I agree Chargry answered my questions in a prompt professional manor.
Good luck with your project!
 
Finally, I love the remote panel - I've run a phone cable from the battery area all the way up to my office so I can keep an eye on the bank from up here without having to turn on a PC or find my phone and I can hear any alert it puts out.

I was looking through the specs and I didn't see anything about bluetooth or wifi. But from the way you phrased this, it sounds like its possible to monitor from your phone/laptop? is this the case? How did you configure this?

I've got BMS16T, mainly because it using external relays for the safety shutoffs is so much better because you can tailor the size of the relay to the size of the load AND replace them if/when they go bad. I also like the external shunt too.

That makes sense, at first I was worried this might be a downside, but now that I think about it (apart from cost) it seems like an advantage.
 
I was looking through the specs and I didn't see anything about bluetooth or wifi. But from the way you phrased this, it sounds like its possible to monitor from your phone/laptop? is this the case? How did you configure this?
The "T" version has a display terminal connected with a phone cord, the one it comes with is a coiled up 8ish footer but it takes a standard phone cable and I had a 30 footer leftover from another project laying around.
 
I just spent two nights reading both manuals for the Chargery BMS8T and the Tiny BMS. They are extremely close in abilities. I distilled it down to the following using info gleaned here at diysolarforum and elsewhere:

The BMS8T:
The manual has lots of Chinese-as-a-first language issues but they're manageable.

The unit appears to be very well done.

The schematics show the relays in the high side and the shunt in the low side. The unit does balance at 1.2A but slows down the balancing if the unit is roasting.

Jason's covered all the bases and ALSO provide precharging with a little board but doesn't actually call it that. Just "Low Current" and "High Current" discharge relays driven from a small board with selectable delay between the Low Current and High Current closing outputs.

Pros:
Does most everything.
Has highest balance out there. 1.2A
Has a built in display/program unit. Once programmed the display is not required, starts up and runs as programmed without it.

Cons:
Doesn't seem to have any wireless status ability what-so-ever.
The display is an annoying blue background but certainly usable.
Only 2 temp sensors.
The standard resistive shunts waste about 15W at 200A. Considerably more than most power relays! (4-10W)

========================

Tiny BMS

Pros:
Seems seriously engineered.
A No Chinglish manual.
Uses a sophisticated LEM (expensive, high quality hall effect type current sensor (loss-less no shunt drop)) The current sensor is a dual unit that has two inside it that switch off with one for sub 70A loads the other for over 70A up to 750A loads allowing a considerable accuracy improvement.
Can do 64(?) temp sensors on a temp sensor comm bus so you can have more than one per battery (if you're psychotic) but at least one per battery is straight forward. (This can quickly clue one in to a problem that could easily shorten a packs lifetime and not be discoverable with only two temp sensors.

Cons:
Puny joke balancing. 150mA**

========================

**There are active balance boards that do nothing but try to keep battery stacks balanced.
Example:r Active Balancer

Possibly install an active balancer on top of the Tiny BMS and get large balancing power. Weirdness is that some of these balancers only balance to the neighboring cell. If a cell's high it's balancer sends the power up to the next cell, then the next, then the next, until the weak one receives the energy. I guess that would work. You would definitely want a BMS watching this to alarm if an active balancer went crazy.

Have heard rumors of cheap active balancers running-a-muck and draining cells well below 2V. May need a way to disconnect the entire A-balancer if the BMS decides the cell voltages are going out of whack.

========================

Note: Lots of talk about chargers of all kinds being extremely pissed-off about having their outputs disconnected while charging. It generally toasts them 80% of the time. To be avoided! So either the BMS should digitally signal the chargers, be them solar or grid, to cease charging and they'd better damn well respond or they need to have their sources opened which doesn't hurt any of them. With a solar charger that means you disconnect the array from the charger or with a grid-tie you dump a relay/contactor that is supplying the grid power to the charger.

I believe I'm going with the Tiny BMS. Ultimately the communications seems very flexible. I could see some off-the-shelf MODBUS server-to-the-cloud working well for a world-wide connection and certainly a local house-net server.
 
I was looking for info on the "serial" ports of the chargery, I don't see anything related to that.....The USB is just for updates? The display connects to main unit with real serial? I wonder why no one has decoded the info yet?

I like the way the evtv.me guy did his AMZ cloud intergrain to his tesla bms reading device.
 
About the Chargery BMS, it's stated in the data sheet that it features over temperature protection and differential temperature protection (between both temp probes I guess, but we don't know what this protection cuts: charge and/or discharge?). But what about low temperature protection, to forbid the charge next to freezing temperatures? It seems like an important need no? Tiny BMS has it, but I can't find it anywhere for the Chargery BMS.
 
About the Chargery BMS, it's stated in the data sheet that it features over temperature protection and differential temperature protection (between both temp probes I guess, but we don't know what this protection cuts: charge and/or discharge?). But what about low temperature protection, to forbid the charge next to freezing temperatures? It seems like an important need no? Tiny BMS has it, but I can't find it anywhere for the Chargery BMS.
From what I understand you set it up to trigger on a "out of temperature range" and you input the high and the low temps.
 
Does anyone (@Steve_S I'm looking towards you) know if the Chargery will play nice with a Samlex Evo inverter/charger, and can take advantage of the Samlex's BMS integration features.

from the samlex manual:
The RJ-45 Jack (6, Fig 2.1) can be used to feed control signals from certain Lithium Ion Battery Management Systems (BMS) that may have capability of enabling / disabling “Stop Charging” or “Stop Inverting” control signals for inverter chargers. This control signal is normally generated by the BMS by switching ON (enabling) or switching OFF (disabling) potential free, Drain (+) and Source (-) terminals of mini Opto Isolated Mosfet Switch [Solid-State Relay (SSR)]. Connect the control signal output from the BMS to RJ-45 Jack
 
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I will NOT be using the Samlex Inverter to charge the LFP pack, it will be charged via the Midnite Classic-200 Solar Controller. I'm doing this because I am keeping my FLA Bank and as secondary power source, until I get some more LFP and panels.
 
I will NOT be using the Samlex Inverter to charge the LFP pack, it will be charged via the Midnite Classic-200 Solar Controller. I'm doing this because I am keeping my FLA Bank and as secondary power source, until I get some more LFP and panels.

Does this mean you are using the Samlex to charge the FLA bank? Or you are using the Samlex with your LFP, but only as an inverter and not using the charging features?
 
From what I understand you set it up to trigger on a "out of temperature range" and you input the high and the low temps.
If you look at the Manuel it states 5C to 30C differential temp of the cells. No low temp capability. (Low temp cut off has been added)
 
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Does this mean you are using the Samlex to charge the FLA bank? Or you are using the Samlex with your LFP, but only as an inverter and not using the charging features?
The Samlex is reserved to charge the FLA Bank when required. The Advantage of the Samlex, is I can setup "Configuration Profiles" and save them to an SDHC card (the remote reads & writes to it) so I can setup one configuration for the FLA and another for the LFP and then switch profiles if needed without a lot of grief.

See my update install in my ShunBin thread as I just got the box finished and is now using the Chargery. As I write this, the Chargery is doing a "Storage" balance. Tomorrow I have to build the "control board" and setup the relays & wiring onto that and get that setup in the powerhouse, as well as "upgrading" the shelf or this 150 Lb pack. This also involves redoing wiring etc for the battery bank as well, which is a full day of work.
 
Just a note for those who use this BMS. If you are installing on a fully charged pack you will not see the coulomb counter work. You need to discharge /charge, After your recharge and it see's power going into the pack does use's the voltage / coulomb counter correctly.
 
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