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Location: Phoenix, AZ

Re: BMS Details

Sorry to dredge up this old thread, but there's a lot of great info here. The schematics as drawn sort of make it look like the monitor for every set of 8 cells is independent, but I'm gathering that this is not really true. From studying the board photos, L50 for example on the far left input of IC32 is really the first of the 4 input inductors on IC31 not a fifth inductor on IC32. So each IC is chained together down the whole line in the same manner that IC33 and IC32 are until you get to the mid point split.

I'm looking at using my 48 Leaf modules in an 8s6p configuration and just want to see if I've got my options straight if I wanted to try and use the stock BMS.

From easiest to hardest:

1. Bypass one section: Use 4 ICs / 17 taps and bypass the rest of the ICs. Each tap will be connected to 6 batteries in parallel, so balancing will be 1/6 as effective as stock.

2. Bypass two sections: Use 4 ICs / 17 taps from each 1/2 of the board, 8 ICs / 34 taps total, bypass the rest of the ICs. Battery would be split into two 8s3p sub packs wired in parallel, each tap will be connected to 3 batteries in parallel so balancing would be 1/3 as effective as stock.

3. Major modification: Use all ICs / taps. Board would have to be modified to cut the connection between the high/low taps after each 4th IC to avoid blowing the trace and/or damaging ICs. Would need to add the missing sense point and filter inductor at the top of each set of 4 ICs. May also be an issue with the comm line between the same 2 chips, i.e. the output of the top chip on one string to the input of the bottom chip on the next string. Might need a level shift? Battery would be divided into six 8s strings in parallel, with each tap connected only to 1 battery so balancing would be as effective as stock.

Thanks for any input,
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Joined: Fri Aug 24, 2018 4:55 am
Delivery Date: 24 Aug 2018
Leaf Number: 022135
Location: Ukraine
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Re: BMS Details

I can't solve a problem. At inclusion or a zaradka of the car in 2-3 seconds it is switched off. Error of P3106 ByPaas Sw. I installed other controller of the battery, but nothing has changed.
In what can be a problem?
Last edited by ybpvin on Sat Mar 27, 2021 6:41 am, edited 1 time in total.
Posts: 1
Joined: Fri Nov 23, 2018 2:14 pm
Delivery Date: 23 Nov 2018

Re: BMS Details

[quote="nikmaster"]I did some experiments. Looks like it can be used for monitoring of 8-96 cells.
Is best to have number of cells dividable by 4. Still did not test the balancing.
I bypassed the the second of the 48 cells and connected 48 only


have there further tests been done to rewire the bms to lower cell count? Will it still balance, has anyone tested that? Sorry for digging that out, this old thread is the best I can find...

I need to rewire the bms for 44s cells. Can I just short out half of the ASICs as you did, and disable one further asic by shorting it's in and out pins? To short out the second half of 48 asics, it just needs the red wire you soldered on the board?

thank you, rostefix
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Joined: Sun Dec 27, 2020 10:28 pm
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Re: BMS Details

After this by pass can we run more Km nissan leaf
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LBC Schematic difference D15110 vs D15120

There is a schematic difference on the LBC board that uses the D15110 chip such as the Calsonic Kansei 285UF00A00 (--C) TC1852.

The chip id is hard wired on pins 22-26 with the "Vcc" [Hi] on pin 27, and pins 20-21 are all tied to "Vss"[Lo], rather than the scheme as shown in the first post of this thread. Pin 26 is wired Hi on all the chips on the top side of the board, and wired Lo on the bottom side.
Last edited by nlspace on Tue Dec 28, 2021 7:09 am, edited 1 time in total.
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Re: BMS Details

What would happend if one would replace service disconnect with in 12 ,24 or 48 V lifepo4 battery?
The bms is isolated so it would not burn out.
would the car run?
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Joined: Thu Jul 07, 2022 5:29 pm
Delivery Date: 08 Jul 2022

Re: BMS Details

Dear Turbo3,

Thank you for your information. I have tried to make the BMS module by Raspberry pi 4, and I refers your information. I have a couple of questions.

First, could you share the link (Here is the link to the PDF:
http://pdf.datasheetarchive.com/indexer ... 511174.pdf" onclick="window.open(this.href);return false;) again?

The PDF version is not opened, and presents with errors as follows:

The error message.
This XML file does not appear to have any style information associated with it. The document tree is shown below.
<Message>Access Denied</Message>

Second, the BMS module operates based on the schematic with the pin numbers?
Posts: 63
Joined: Mon Sep 30, 2019 2:44 am
Delivery Date: 01 Dec 2018

Re: BMS Details

Turbo3 wrote: Thu Feb 19, 2015 11:53 am On LeafSpy Pro you must select BMS as the model year in settings.
Thanks Turbo,
Was what needed to know also to connect direct to battery
Your App has been very help full for know how good batteries are.
I even used the re-pair feature few weeks back for swap

1,000% good tool to have
Posts: 63
Joined: Mon Sep 30, 2019 2:44 am
Delivery Date: 01 Dec 2018

Re: BMS Details

@Turbo3 is their any why to use Leaf Spy to scan a Gen1 battery (2011/2012)

I tried on Gen2 and works well
But when I rewired for a 2012 battery does not get any readings
Posts: 1
Joined: Mon Mar 13, 2023 6:00 am
Delivery Date: 13 Mar 2023

Re: BMS Details

Hi, I try to restore burned BMS after cell splitting.

I have changed burned Asic from another BMS (both 30kwh) and few other visually burned resistors, capacitors etc.
Tested circuit in damaged Asic (IC28) block - all good
Tested three photocouplers - all good

Still getting -Cell cont LIN error and -Cell cont Asic1-24
It looks like there is a problem in a whole Asics circuit and Lin communication.

Would be helpful for any ideas what to look for.
Also question: are all ASICs the same? Maybe they have some kind of info data written inside (LIN, ID etc.)?

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