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Recommend non-Daly BMS for 200A?

jspencerg

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Jan 22, 2021
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Hello,
Looking for BT and PC connections. I see choices on Aliexpress, but want to know package works. Are you having good results with your BMS?
 
I have used several BMS, with various results.

ANT BMS seems to hold on quite good, at higher amperage the voltage drop will course heat (and energy loss)

I haven't heard negative from electrodacus, no hands on experience.
(I've been active member for quite some time, for sure I would have seen it if there where issues)

The QUCC seems to be OK.
New version have better contactor.

Chargery is good, and you choose your quality Contactors.

DIYBMS, what require soldering and flashing firmware.
Open source, WiFi, BT, canbus, UART, all the toys you can wish for.

Upper price class:
Batrium.

A cheap AliX 400A contactor is about $50,- and uses continue 7 watt.
The quality type is about $175,-
And uses about 4 watts.

Just to give you an indication on what to expect.

Batrium starts at $500, but does include quality Contactors.
 
fhorst: That is a large list. Perhaps you can help me narrow it down? I'm building 4s4p lifepo4 battery which should have 210AH(using eve cells). I thought 200A would be appropriate for battery size and the 2kw inverter i have. Thanks.
 
4S,4p, 12v.
2000 watt inverter is roughly 85% efficient, so you draw 2350W@12.8v, about 185A.

Do you use 2000w?
If the answer is seldom, and usually 750-1000 watt, Mosfet based might be a good choice.
(Daly 250A smart)

The QUCC seems to fit here in the middle.

If you plan to use regular +1000 watt, Chargery is the better option.
For Contactors, depending on your budget.
The +$125-175 type will outlive your LiFePO4 setup.
The $50,- type you might want to buy a spare.

As you see, higher amperage usage does increase the cost.

Without insight on the budget and your expectations for lifecycle, it's hard to give advice.

Batrium and victron you "can't lose".
But they will cost you.

How much is trouble free protection of your investment worth?
 
I bought a 250A Daly with BT and usb. Company store sold me stock made in fall 2019. Died after 3 days of trouble filled use. Might get replacement, might get money back, might get screwed.
I'm committed to 2KW inverter as backup if grid goes down. Can also connect inverter to prius. Building battery predominantly for extended camping needs, but want higher amp capability.
I can put together any cables, so no need for included connectors.
BT, USB and reliability are key.
Thanks.
 
How many TOTAL max amps are you expecting to pull out of your battery bank?

With a 4s4p arrangement you could easily achieve 480 amps of charge/discharge amp capacity using an Overkill Solar 120 4s BMS on each 4s battery.

Daly is probably one of the last BMS that I would use. Too many issues. Too much quantity, not enough quality.

The Overkill Solar BMS has proven to be reliable with a good feature set. However, due to its popularity, it sells out as soon as inventory is replenished.
 
Yeah. Quickly discovered Daly issues when went to forum as my troubles began.
I have a 39L pelican-style case from HF for battery, so don't want to accommodate multiple BMS.
Going with 200-250A possibility for inverter use. Don't have any higher amperage needs.
 
I'm not sure i understand your point. Cells are new and well matched so not worried about parallel balancing issue
 
I'm not sure i understand your point. Cells are new and well matched so not worried about parallel balancing issue
4ps4 is a single 12 volt battery.
4s4p is 4 discreet 12 volt batteries each with its own bms.
 
That's a 2p4s configuration. The nomenclature can be a bit confusing at first.

The need for more amps (not Ah) is why I split my 8 cells into two 4s batteries, each with their own BMS. I have 240 amps of throughput.
 
I think my box limitations preclude using 2 BMS. Just one large BMS and depend on good cell matching and peformance. Plan to use conservative charge settings.
 
I don't have any experience setting up a 12V pack, but based on everything I've read on this form, if I were going to build a DIY 12V battery, I would probably go with an JBD (Overkill) 120A BMS (one per 4S pack). At 12V, having two batteries in series just makes a lot of sense to me (lower operating current, individual cell-level balancing/protection, and for the redundancy).

If you really can't make 4p2S work (ie, you're sticking with 2p4S), and you need to push 200A continuously, seems like something with external relay control may be the way to go. That said, Heltec offers 200+ amp Mosfet-based options, but if you really need bluetooth and PC connectivity, you're going to pay well over $200 after shipping.

EDIT: Doesn't look like Heltec's "smart" BMS comes in anything less than a 13s configuration, so that's a no go...
 
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See spec's below. Would need extra heat sink plate for high current use. Any experience with similar?

Found on aliex: QUCC BMS 4S Lifepo4 200A 250A Lithium Battery Protection Board Charging Equalizer 18650 bms 12V with Balance Temperature Control. $106
 
I think I'll reconsider possibility of installing two overkill 120A units.
My plans depend on how Daly responds to their unit's failure...
 
Not sure what you were looking to use the Bluetooth/PC connections for, but another path to consider would be to use a 'dumb' BMS along with a separate 'smart' battery monitor. A 4S-100A BMS from JBD is only $20 on AliExpress. Two of those (for a 4p2s configuration) plus a smart shunt (example) might get you the features you were looking for.
 
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