New JBD mini 7S-14S 30A BMS with switch, temp, BT, UART

[Tomblarom]

I needed a small BMS for a project and discovered, that JBD made a new ultra compact smart BMS! It's only 63*52*12mm and has has all these common features!

• 7S to 14S (automatically configuring)
• Continuous 30A, Peak 90A (for 1s)
• Type: Li-Ion (3,7V) or Lifepo4 (3,2V)
• Size: 63*52*12mm
• Mosfets: PES016N08R (2x on 20A, 4x on 30A, 6x on 50A)
• Features:
  • Hardware switch
  • Tempsensor
  • Integrated Bluetooth on PCB
• Protocol: UART (or CAN with adapter.. "Fake CAN")
• App: Xiaoxiang, Software: JBD-Tools

15$ is a reasonable price for 14S BMS under 30A..!

Available here: https://www.aliexpress.com/item/1005004892183305.html
What do you think? Perfect for e-scooter or e-longboard builds!

Images from customers (not me):

 

[dominik h]

I installed one last year and today another one. They dropped the price, very nice.

It has one downside.
I charged my 8S20Ah Lifepo A123 with 20A and it stopped charging because one cell reached 3,65V. The others are 0130-0,2V behind and the bms also stops balancing after this Event.
Normaly a bms stops charging and then balancing goes on.
Tomorrow I will try to get the cells together with a low current charge.

 

[dominik h]

No more downside, found my error in the settings. You have to disable
"charge balance"
to have the balancing working all time.
If it is enabled it balances only when charging, so the balancer could not drain the battery.
But If you want to make a first equalization of your cells you have to turn this function off.

 

[dominik h]

Pictures of the 30/90A version
I killed one , when I changed my charge plug from 2 poles to 4 poles.
Made a perfect short circuit, the contacts in the plug got vaporized.
The 6000A short circuit current was too much for the mosfets.
The installed A123 Lifepo Pouch battery has 2V sag at 500A.

 

[Tomblarom]

I was looking for the use of the STX and found the PDF, that's attached. According to it, the STX pin is a 1-wire communication line for sending and receiving data.

Additionally I attached the PDF for further reference and because I wasn't able to find it elsewhere.

I just spotted they the either completely switched to DP023N10TGN MOSFETs (datasheet attached) or just use them for the 50A version.

 

[neptronix]

Amazing that you can get an actual functioning BMS for $15.

But is there the gotcha where the BMS draws off 1 or 2 cells, eventually wearing those cells out over the long term?

 

[dominik h]

I charge the A123 20Ah Pack five to six times a year and I haven't seen any discharged cells yet.

 

[A-DamW]

But is there the gotcha where the BMS draws off 1 or 2 cells, eventually wearing those cells out over the long term?

I own several of the 14s SP14S004, and 17s SP17S005 nodels, two of each installed on four 13s packs from July-2024, so 12mo of data.

One pack is on my daily driver and gets cycled regularly, I have not observed any noticeable deviation/drift of cells 1-2, or any other cells.
No balancing at all, other than the initial manual one from July-2024.

The other 3 packs have had zero balancing or charging, same voltage as received from Batteryhookup, minus a few tens of milivolts of self discharge.

These are the 3 packs that I used to develop my vesc compatible BMS project so they have sat for days on end actively transmitting Bluetooth data, and I have not noticed any cell drifting.

Fyi, the bluetooth/bms chip seems to go into deep sleep about 30 seconds after disconnecting from bluetooth.

 

[neptronix]

Okay, i think i'm a JBD BMS fan now.

 

[TPEHAK]

Okay, i think i'm a JBD BMS fan now.

Brand-wise I use a couple different JBD BMS models in a couple batteries and they work just fine. They had some glitches detecting amount of batteries cells during initial installation, but unplugging and plunging back the balancing leads sorted things out. The original JBD Android application does not work quite well so I use different application (Overkill Solar) to check the batteries and it works fine.

 

[Tomblarom]

JBDs are my goto when building batteries, because space is always limited.. When using ABS-cases from Reention (DP-6, DP-9, ..), it's common to spare out a few cells, to leave room for a BMS. With JBD, you can even use them without the aluminium plate, because the heat is dissipated decent enough. I draw ~50A like this, with SP15S020:




Another build, with SP14S004:

 

[Diggs]

In typical Aliexpress bait-and-switch tactics it's not a $15 but $22+ for anyone that has ever bought at Aliexpress before. They show one price but it's always higher for previous buyers at checkout. Aliexpress is so disappointing.... JBD Smart BMS are available on Amazon and Ebay quicker and for not much more money. (/rant off)

 

[Zambam]

In typical Aliexpress bait-and-switch tactics it's not a $15 but $22+ for anyone that has ever bought at Aliexpress before. They show one price but it's always higher for previous buyers at checkout. Aliexpress is so disappointing.... JBD Smart BMS are available on Amazon and Ebay quicker and for not much more money. (/rant off)

$15 price was from Mar 24. Lot's has changed since. There's also many "color" choices which can change the price. Price is different depending if you are logged in or not. They offer first time buyers a huge discount like more than 50% for a 1st time purchase.

 

[dominik h]

They now offer a 50A/150A Version

 

[braunschweiger]

Fyi, the bluetooth/bms chip seems to go into deep sleep about 30 seconds after disconnecting from bluetooth.

I never seem to get a second BT connection once it has gone into deep sleep. Any known fix?
(my bms says version 32)

 

[braunschweiger]

I never seem to get a second BT connection once it has gone into deep sleep. Any known fix?
(my bms says version 32)

Solved. OKsolar does not seem to randomly loose connections and is able to awake the sleeping BT.
Both 'BJD bms' 1.10.4 and 'XianXing' 3.2.060 would only randomly connect, show not much info in guest mode, not allow configuration, drop connection at random, require power cycling for reconnecting attempts.
Thanks to this forum for some kind soul mentioning the OverKillSolar app.