DALY BMS Teardown & Failure Review (16S 40A)

[methods]

* I don't know anybody at battery hookup
* I didn't get any kind of discount or promo
* I bought my stuff with my own money
* I bought based on a reference I got on this forum

* I don't sell anything
* I don't sell any service
* I don't care if you burn your house down
* I don't care if you burn your mom's house down

All I want to do is find a BMS that is safe for us to use for our solar activities.

* A cheap BMS that is reliable

-methods

 

[methods]

1hr @ 20A open air room temp
I can feel the BMS is warmer than the surfaces around it. I suppose if you wrap it up and duct tape it could overheat, especially at 30 amps.

All of these open frame BMSs need to either have some air flow or they have to be sunk to case. Sinking the case would of course be best.

* Pausing the test halfway through

-methods

 

[batteryGOLD]

does even the low cut voltage works?
there are many bms from DALY with some little issue, the low cut voltage does not work!! similar to small issue at onewheel, some times throw person out of tha board! this is only at some special cases.. but happens.. most people owning onewheel is happy with it and trust it! and do U believe in missel ghost? out of topic..

so allways do full dischrge test to any battery that is using DALY bms, and ensure that never passes lower limit level..
it happens to me a 67V goes discharged to 15V..

But if you are the type of person that only goes to min20%or 10% charge state, you dont need to worry about this issue, battery would never go under low cut voltage..unlessss some debalanced cells..

Hope those DALY having higher cut voltage working..I've tested just one DALY 16S and is OK
Today, something dangerous happened at LAB, I was doin quick 5A charge to a battery 14S with power supply constant current.
The battery cell blocks went up to 4,6V , this meaning the BMS noO cutting at top! that was a withe brand bms.
the battery max 58,8V went up to 64,4V and did not fire or explode! maybe safe overchrge at those cells.. after a full discharge I got more 20% capacity, soo charged from max 4,2 to 4,6V it will give +20% capacity. Does worth the risk?
NEVER DO OVERCHARGING!

soo allways check if your bms does top cut, if not U could get into troubles!

 

[methods]

I finished testing the Battery Hookup 16S 30A Common port LifePo4.

$26 Good Value / High Quality
https://batteryhookup.com/collectio...s-30a-bms-with-balance?variant=42283333648546

Its fine for use
It tolerates abuse

The balancing is excruciatingly slow but that is fine and normal. The LED's will show you that it is doing its work and it does not require >58V to keep balancing. With a grossly imbalanced pack it worked all night without the charger plugged in. I could detect the balance heat but just barely. Very low current, nothing that would overheat it if packed.

[youtube]zTjSoykEOco[/youtube]

It did not stop short circuit but was also not damaged, @ 22awg direct short. I usually do this with 12AWG on a different setup that has a lot of strikes on it. Maybe if I tried this there it too would stop the discharge within 500uS like my higher current BMS's do. For something like a 100A BMS, it really should be able to terminate a short like this and hold it off for a few seconds.

For this little one... it has the current detecting resistors but seems to ignore them. At least in very basic street testing.

[youtube]GP4ERFS6kfA[/youtube]

It did not stop short circuit across anodized aluminum, but it was not damaged. All normal tests passed after the short circuit test and that is what I really care about. You do not want to tap wires together and have your BMS mosfets go short on you. You can tell they have if it suddenly runs hotter than normal in charge or discharge AND/OR it fails to terminate a charge or discharge.

[youtube]OrUoq3mYWvU[/youtube]

It did not stop 1min of discharge at over 60A, but it was not damaged and did not get over 45C. I am somewhat disinterested in further testing as this is a BIG PASS for only $26.

.. pulling up the notes

LVC hit at 2.3V and released at 2.5V
VchargeBlock was at 1.3V, below that it will not charge
In use I did not see much more than 3.7 or 3.75V on any cell while doing other tests

All of the LVC tests tripped
I did not dig hard into HVC (I need to get out my supply) but Charge and Discharge terminate for over temp External and Over Temp Internal. I have every confidence that it would execute on an HVC event.

I am happy with it, moving forward
Application was some 1C 30Ah packs. They are rated to discharge 30-60A and charge at 15A. I have them massively ganged parallel in at least 5P.

My rig can do 200A Charge or Discharge now, so I will probably bump out to at least 10P. This can be problematic a 1, 3, 5 units fall off or lock up. In that event you are now depending on thermal in a lot of ways. Its pretty sketch. Seems like you should just upgauge but that does not work out practically.

* Fuses

Just fuse for your wires and it will be fine. Breakers tend to fail, so simple old fuses rated for at least 60V. I use 10AWG so 30A fuses. Yea they may pop, but that is better than having to characterize every failure mode that may result in 1 or 2 or 3 or 4 units seeing 2X or more continuous charge or discharge.

I... would really prefer a BMS that has programmable limiting... but that costs more than $26... and this is dragging out so long that I am about to go back to running NO bms.

-methods

 

[methods]

Here is the length of the overcurrent test.

[youtube]Vk7Czs8gw1w[/youtube]

-methods

 

[methods]

Conclusion

For under $30 you get a MUCH BETTER VALUE from the BMS available at Battery Hookup than from the DALY unit sold on (non prime) Amazon. I am absolutely positive that I got "Ripped Off" by the Amazon seller and the DALY BMS that arrived was not only poor quality goods, but

* Dangerous Goods
* Hazardous Goods
* Latent Failure Goods
* Counterfeit Goods

When I get the pictures compressed and show you the differences in BUILD QUALITY it will be apparent

DALY non-pop on protection diodes
BH had them

DALY made from recycled parts
BH all new

DALY made from unknown garbage mosfets that just fail
BH had 25V margin and performed in a way that indicated that they are what they say they are

DALY looked pretty
F-That bro, that is bullshit

BH was conformal coated, easy to inspect, easy to repair, a bit more fussy, tolerant of burst current, arrived as described. Overall the two are not in the same leauge.

DALY == B U N K
BH == Hooked me Up

I got hooked up

-methods

 

[fechter]

Thanks for testing. I love the balancing LEDs on the BH unit. The short circuit test is important and glad you didn't burn your fingers testing. The wire didn't fare so well.

 

[CONSIDERABLE SHOUTING]

Thank you so much methods! Good to hear BH has such a quality BMS at such a low pricepoint.

 

[batteryGOLD]

* Dangerous Goods
* Hazardous Goods
* Latent Failure Goods
* Counterfeit Goods
-methods

plus
*slavery production work (all electronics/clothes production have this root issue..)
*very low salary to production workers
*repetitive work to build (keeps worker dumb and limited professional career)

and also remember low level work to get raw materials
silicon for chips, lithium, cobalts etc etc.. those people working at mines having hard times and die early because breath health problems or other issues..(remember at mines they have a bird inside a cage to monitor air quality, if bird suddenly dies, get away from that mine ASAP! )

shipping logistics success solutions became a problem! a lot of CO2 + CO + other extreme toxic elements released to atmosphere + oil leaks to water by cargo ships(remember product has to travel thousands of miles, cargo ships are a known earth pollution/disturb problem. low frequencies sounds emitted by motors, disturbs all animals hundreds miles around cargo ship, some die because very loud motor sound under water, and some go away/get lost of natural route! too many dB's under water!!!)
thats a lot of stuff happening behind of the scenes just to have a nice beauty final product that amazes consumer! We need to be happy!

more problems.. what happens to electronics after use/end of life? those go trash to poor countries, and recycling is hard of any kind of electronics.. or we can send trash to space. but do you want to pollute space??

I just want to have all tha stuff tha money can buys! (contradictory)
Anyway we dont need to be extremist thinkers based on reality! mines are a great place for tourists visit plus artistic pictures!


By the way, very detailed bms testing at a very knowledge technical level, plus educative content! Thanks

HAPPY XMASSS to all

 

[Bbbbrass]

Revisiting this after a few years of usage. While these BH JBD "dumb" BMS have been working well, I'd love to add more temp sensors and BT. Well, I found this unit on Amazon for basically the same price ($25 shipped/tax). Building a new 14S3P 21700 pack for a TSDZ2B mid drive, and this will let me monitor temps and draw without having to open up the pack to get to the balance leads. I'll let you know how it goes...

I am a bit concerned there are only 2 Mosfets, compared to the number included on the "dumb" unit. This seems to be the chip info, but I can't find anything on it.
PES016ND8R

 

[eee291]

I've used these newer and smaller JBD BMS without issue.
The fully populated one can do 130A without getting hot, so one of these MOSFETs can easily handle 20A continuous.

 

[A-DamW]

Revisiting this after a few years of usage. While these BH JBD "dumb" BMS have been working well, I'd love to add more temp sensors and BT. Well, I found this unit on Amazon for basically the same price ($25 shipped/tax). Building a new 14S3P 21700 pack for a TSDZ2B mid drive, and this will let me monitor temps and draw without having to open up the pack to get to the balance leads. I'll let you know how it goes...

I am a bit concerned there are only 2 Mosfets, compared to the number included on the "dumb" unit. This seems to be the chip info, but I can't find anything on it.
PES016ND8R

Link for mosfet specs:
viewer

 

[Bbbbrass]

Link for mosfet specs:
viewer

Thanks for that! That doesn't look too bad. I do wish there was more than 1 per busbar, but I feel a bit better that it's something with an actual data sheet.

 

[Bbbbrass]

I failed to use the proper wiring, since the BMS came with no instructions. I (wrongly) assumed it would be like the previous “universal” JBD wiring I had used. This is the correct way for the 10-17S balance leads.

 

[Bbbbrass]

Well, not an auspicious debut. Hooked up to my tsdz2b, and it gives a low battery warning as soon is it grabs power. Pack still gives power on the light circuit, so it’s looking like over current trips even though I set it to 15amp max in the vlcd5. Old battery with dumb bms works fine, except testing the balance while charging it I was careless with my probes and shorted it. Big spark and now with leads connected it won’t go above 11V. It’s been so long I can remember if I short it to restart it? Connecting the charger doesn’t change anything.