Info on BMW hybrid battery packs?
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
Has anyone installed these modules on their side rather than flat? Is there a good reason not to do so?
- chrskly
- Posts: 149
- Joined: Fri Feb 21, 2020 5:04 pm
- Location: Dublin, Ireland
- Has thanked: 39 times
- Been thanked: 38 times
- Contact:
Re: Info on BMW hybrid battery packs?
I guess since they're cooled out the bottom plate you might want to have their bottoms touching the outside wall of the battery box. Not that they get very hot by all accounts (not firsthand knowledge).
Christian
My 1965 Ford Mustang project
chrskly.com
My 1965 Ford Mustang project
chrskly.com
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
This was my thinking. But the temps really don't seem to change much, at least on charging. I've only charged at 8A so far but the temperatures didn't move more than a degree.
If I can rotate the modules 90 degrees I can fit five side by side between my chassis rails, saving a load of space in the engine bay and lowering the weight down in the car. Might give it a try.
- Jack Bauer
- Posts: 3563
- Joined: Wed Dec 12, 2018 5:24 pm
- Location: Ireland
- Has thanked: 1 time
- Been thanked: 87 times
- Contact:
Re: Info on BMW hybrid battery packs?
I covered the temperature issues on the BMW hybrid packs of the conversion courses. Here is a short version : ask yourself what is different about how we (bev) builders use the packs versus how bmw (phev) use them...
I'm going to need a hacksaw
- chrskly
- Posts: 149
- Joined: Fri Feb 21, 2020 5:04 pm
- Location: Dublin, Ireland
- Has thanked: 39 times
- Been thanked: 38 times
- Contact:
Re: Info on BMW hybrid battery packs?
Of course, I remember the wiggly graph.Jack Bauer wrote: ↑Mon Aug 09, 2021 9:39 am I covered the temperature issues on the BMW hybrid packs of the conversion courses. Here is a short version : ask yourself what is different about how we (bev) builders use the packs versus how bmw (phev) use them...
Ignore me, this is an irrelevant suggestion.
Christian
My 1965 Ford Mustang project
chrskly.com
My 1965 Ford Mustang project
chrskly.com
Re: Info on BMW hybrid battery packs?
My front pack they are mounted on the side, and they front pack is normally 3 degrees cooler than the rear pack in the boot
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
Fantastic - thank you. This is going to massively improve my layout.
Re: Info on BMW hybrid battery packs?
I might be getting away with it though due to spreading the load cross the 3 paralleled packs! But I’ve just driven to work, ambient temp is 17, front pack temp 17 rear pack temps 19 inverter temp 19
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
I wasn't getting above 21 when charging - albeit not fast charging - so that seems pretty inline with what I'm getting.
Re: Info on BMW hybrid battery packs?
I got the rear battery pack up to 38 charging with 3.3kw obc but that is inside the boot with the air cooled charger inside a black car when it was about 28 degrees outside, will have to look while charging at night
- celeron55
- Posts: 776
- Joined: Thu Jul 04, 2019 3:04 pm
- Location: Finland
- Has thanked: 29 times
- Been thanked: 110 times
- Contact:
Re: Info on BMW hybrid battery packs?
Living in Finland, the first thing I really want to know about batteries is in what temperature they can be charged. I'm planning to use these without active heating, so I needed to find some source of information.
Well, the closest I could get was a datasheet for some Samsung SDI 94 cells, which I guess are used by BMW in the i3. I think these PHEV cells are the same series, but with less energy density and more power density. I'm going to assume these can take about half the charge current of those 94Ah cells:
I think these are pretty good batteries for cold climates, as they can always be charged, albeit with lowered current. No need to waste energy heating them just to charge them.
Even so, if you have just a measly 3.3kW charger, you don't need to even think about current limits before -25°C, which is really nice. You do need to be aware of this for regen though, pretty much right at 0°C.
Here's where I found the datasheet: https://shop.gwl.eu/Samsung-SDI94-NCM/L ... g-NCM.html
Well, the closest I could get was a datasheet for some Samsung SDI 94 cells, which I guess are used by BMW in the i3. I think these PHEV cells are the same series, but with less energy density and more power density. I'm going to assume these can take about half the charge current of those 94Ah cells:
I think these are pretty good batteries for cold climates, as they can always be charged, albeit with lowered current. No need to waste energy heating them just to charge them.
Even so, if you have just a measly 3.3kW charger, you don't need to even think about current limits before -25°C, which is really nice. You do need to be aware of this for regen though, pretty much right at 0°C.
Here's where I found the datasheet: https://shop.gwl.eu/Samsung-SDI94-NCM/L ... g-NCM.html
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
That's really good to know, thanks. Doesn't get so cold here (Northern England), just very wet. Nonetheless reassuring.
Re: Info on BMW hybrid battery packs?
Does these battery packs specifically 330e has current sensor and simpbms can read it?
-
- Posts: 50
- Joined: Fri Jun 26, 2020 7:25 pm
- Location: West Sussex, UK
- Been thanked: 2 times
Re: Info on BMW hybrid battery packs?
The SBOX spits out CAN messages that give you current and voltage for the pack and DC bus.
Attached is a DBC file for SavvyCAN that can de-code it.
There is a picture in an earlier post from me on page 8 in this thread on how to connect 12V and get to the CAN bus. Note, the Can H and Can L may be swapped in that picture - I can't remember now.
Tom should answer if SimpBMS can now read SBOX messages. The version I'm modifying does not.
I've connected the modules and the S-BOX together on a CAN bus, connected to SimpBMS. They can co-exist, but there is a shared use of message ID0x200 unfortunately, which is the S-BOX current - how unlikely was that! Anyway, the 0x200 from the CSCs, as far as I've noticed always, has 0 for bytes 5 6 7 whereas the S-BOX message never seems to have that, so they can be separated.
FYI, this is how I've modified SimpBMS to use the S-BOX current:
Then to decode the CAN message:
This is untested other than it compiles, runs and displays the current from the SBOX sensor when it should correctly, but not tested in a working vehicle. If anyone is interested, pack and DC volts can also be de-coded and used if desired. I'll use this for pre-charge and contactor management.
If you do test this for real, please report your findings! I'm getting closer but still not at connecting the HV stages yet!
Thanks again to Tom for sharing the SimpBMS code.
Attached is a DBC file for SavvyCAN that can de-code it.
There is a picture in an earlier post from me on page 8 in this thread on how to connect 12V and get to the CAN bus. Note, the Can H and Can L may be swapped in that picture - I can't remember now.
Tom should answer if SimpBMS can now read SBOX messages. The version I'm modifying does not.
I've connected the modules and the S-BOX together on a CAN bus, connected to SimpBMS. They can co-exist, but there is a shared use of message ID0x200 unfortunately, which is the S-BOX current - how unlikely was that! Anyway, the 0x200 from the CSCs, as far as I've noticed always, has 0 for bytes 5 6 7 whereas the S-BOX message never seems to have that, so they can be separated.
FYI, this is how I've modified SimpBMS to use the S-BOX current:
Code: Select all
void canread()
{
Can0.read(inMsg);
// Read data: len = data length, buf = data byte(s)
//update this for S-BOX
/*
if (inMsg.id == 0x3C2)
{
CAB300();
}
*/
// Updated for S-BOX CAN messages (assumes S-BOX is OK sharing with the module CAN bus 0)
//ID = 200 Current
if (inMsg.id == 0x200)
{
SBOXcurrent();
//Serial.println("S-Box Current Received!!!!! &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&");
}
//ID = 210 Pack Voltage
if (inMsg.id == 0x210)
{
SBOXbatVoltage();
//Serial.println("S-Box Bat Voltage Received!!!!! &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&");
}
//ID = 220 DC Bus Voltage
if (inMsg.id == 0x220)
{
SBOXdcBusVoltage();
//Serial.println("S-Box DC Bus Voltage Received!!!!! &&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&&");
}
...
Code: Select all
// ID 0x200 Pack Current +-mA
void SBOXcurrent()
{
// make sure to reject the ID0x200 message sent from the CSCs, which always has 000 for bytes 5,6,7
// we only want to process ID0x200 measages from the S-Box
// Unlucky both use ID0x200 but luckily very easy to separate:
if (!((inMsg.buf[7] == 0) && (inMsg.buf[6] == 0) && (inMsg.buf[5] == 0)))
{
//must be from S-BOX current so process:
inbox = inMsg.buf[2];
inbox = (inbox << 8) + inMsg.buf[1];
inbox = (inbox << 8) + inMsg.buf[0];
if ((inMsg.buf[3] & 1) == 1)
{
CANmilliamps = inbox - 0xFFFFFF - 1;
// may need to get rid of -5mA offset I see at zero current
}
else
{
CANmilliamps = inbox;
}
//Serial.println("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$");
//Serial.print("S-BOX Current: ");
//Serial.println(CANmilliamps);
//Serial.println("$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$");
//Serial.print("mA inbox = ");
//Serial.println(inbox);
if (settings.cursens == Canbus)
{
RawCur = CANmilliamps;
getcurrent();
}
if (candebug == 1)
{
Serial.println();
Serial.print(CANmilliamps);
Serial.print("mA ");
}
}
}
If you do test this for real, please report your findings! I'm getting closer but still not at connecting the HV stages yet!
Thanks again to Tom for sharing the SimpBMS code.
- Attachments
-
- Sbox no offset.zip
- (652 Bytes) Downloaded 135 times
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
Realised no-one answered this and I have the same question. I'm charging to 4100 at the moment but wondered about going higher.
Re: Info on BMW hybrid battery packs?
I have charged to 4150 with no noticed I’ll effects but as the car is of the road until the new motor and inverter setup in finished I can’t test further
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
Going back to the original limits of the pack as suggested earlier in the thread, I'm thinking about sticking between 3000 and 4000
Pack voltage | Cell voltage | SoC (notional)
332 4.15 100%
321.2 4.015 90%
310.4 3.88 80%
288.8 3.61 60%
267.2 3.34 40%
245.6 3.07 20%
234.8 2.935 10%
224 2.8 0%
Re: Info on BMW hybrid battery packs?
You can certainly try, but my experience was they start falling rapidly at 3.3v so in practice I was only discharging to 3.4v
- bobby_come_lately
- Posts: 466
- Joined: Sun May 03, 2020 5:39 am
- Location: Manchester, UK
- Has thanked: 37 times
- Been thanked: 39 times
- Contact:
Re: Info on BMW hybrid battery packs?
Ah OK. That might explain my accidental extreme range test. Thought my pack might have been a bit degraded but maybe it's just that.
Doesn't give a huge amount of range.
Doesn't give a huge amount of range.
Re: Info on BMW hybrid battery packs?
Maybe it’s a degradation thing also, my 3 packs paralleled are all either 2016 or 2017 modules and the cell dela at rest after balancing is 3-6mv thought that 4.1- 3.4v range then grows quickly to worrying numbers, guess that’s top balancing for you
Re: Info on BMW hybrid battery packs?
Has anyone noted the model/rating of the HV fuse in the newer sbox? (with the orange contactors) Thanks!
Re: Info on BMW hybrid battery packs?
I checked my bmw hybrid with diagnostic tool and I see that charging ends at 4.15v.
Re: Info on BMW hybrid battery packs?
Apologies if the answer to this question is obvious - I’m learning as I go! - the 5v line appears to be taking its voltage from the teensy vin pin - I thought this was 3.3v max when powered by usb? Have a missed something obvious or is 3.3v actually enough for the 5v line?OutlandishPanda wrote: ↑Thu Jul 09, 2020 7:54 am Got to my pack, connected a MCP2562 transceiver to a Teensy 3.2, loaded SimpBMS BMW PHEV as per Tom's posts above (latest version) and connected as below. Success!! I can see all the modules and cells and its a healthy pack. Couldn't test balancing as my pack seems well balanced (2mV delta), which was a surprise given it has sat untouched for many months. I assume it can't balance disconnected from the vehicle?
A few pics of my setup and links if that is any help to anyone below.
Transceiver (I used 2562 and connected VIO to 3.3V):
http://ww1.microchip.com/downloads/en/D ... 05167C.pdf
Tom's code:
https://github.com/tomdebree/BMWPhevBMS
I disconnected the BMW BMS and connected in to the blue connector: PHEV CAN2b.jpg
You can see from this picture of my breadboard I had to terminate the CAN lines at the transceiver with 120R.PHEV CAN3.jpg
The 3 first modules power and CAN is separate from the last 2, so needs two sets of 5V connections.
The CAN lines for the 3 and 2 module sets also "seem" to be separate, measuring the continuity of the CAN lines to the modules and this connector, but only one of the CAN lines for the first three modules needed to be connected to be able to see them all on that CAN bus. No idea how/why, but seems to work fine and means termination is easier. Perhaps I measured it wrong.
The 5V line takes about 64mA when enabling all 5 modules, so probably also powering some of the logic of those boards.PHEV CAN1.jpg
The output I recorded was:Very happy with that. The voltages all moved around a tiny bit over time, so they were "live". Now working on a very simple display to connect in to the Teensy to help with debugging on the bench and sorting out the contractors etc. and adding a simple mode change button.Code: Select all
BMS Status : 1 Ready 80 Out:0000 Cont:0000 In:0000 Charge Current Limit : 10 A DisCharge Current Limit : 30 A Modules: 5 Cells: 80 Strings: 1 Voltage: 289.420V Avg Cell Voltage: 3.618V Low Cell Voltage: 3.617V High Cell Voltage: 3.619V Delta Voltage: 2mV Avg Temp: 19.600C Module #1 57.89V Cell0: 3.62V Cell1: 3.62V Cell2: 3.62V Cell3: 3.62V Cell4: 3.62V Cell5: 3.62V Cell6: 3.62V Cell7: 3.62V Cell8: 3.62V Cell9: 3.62V Cell10: 3.62V Cell11: 3.62V Cell12: 3.62V Cell13: 3.62V Cell14: 3.62V Cell15: 3.62V Temp 1: 21.00C Temp 2: 20.00C Status: 0x0 Bal: 0x0 Module #2 57.88V Cell16: 3.62V Cell17: 3.62V Cell18: 3.62V Cell19: 3.62V Cell20: 3.62V Cell21: 3.62V Cell22: 3.62V Cell23: 3.62V Cell24: 3.62V Cell25: 3.62V Cell26: 3.62V Cell27: 3.62V Cell28: 3.62V Cell29: 3.62V Cell30: 3.62V Cell31: 3.62V Temp 1: 19.00C Temp 2: 21.00C Status: 0x0 Bal: 0x0 Module #3 57.88V Cell32: 3.62V Cell33: 3.62V Cell34: 3.62V Cell35: 3.62V Cell36: 3.62V Cell37: 3.62V Cell38: 3.62V Cell39: 3.62V Cell40: 3.62V Cell41: 3.62V Cell42: 3.62V Cell43: 3.62V Cell44: 3.62V Cell45: 3.62V Cell46: 3.62V Cell47: 3.62V Temp 1: 20.00C Temp 2: 19.00C Status: 0x0 Bal: 0x0 Module #4 57.89V Cell48: 3.62V Cell49: 3.62V Cell50: 3.62V Cell51: 3.62V Cell52: 3.62V Cell53: 3.62V Cell54: 3.62V Cell55: 3.62V Cell56: 3.62V Cell57: 3.62V Cell58: 3.62V Cell59: 3.62V Cell60: 3.62V Cell61: 3.62V Cell62: 3.62V Cell63: 3.62V Temp 1: 18.00C Temp 2: 19.00C Status: 0x0 Bal: 0x0 Module #5 57.88V Cell64: 3.62V Cell65: 3.62V Cell66: 3.62V Cell67: 3.62V Cell68: 3.62V Cell69: 3.62V Cell70: 3.62V Cell71: 3.62V Cell72: 3.62V Cell73: 3.62V Cell74: 3.62V Cell75: 3.62V Cell76: 3.62V Cell77: 3.62V Cell78: 3.62V Cell79: 3.62V Temp 1: 20.00C Temp 2: 19.00C Status: 0x0 Bal: 0x0 CANbus 0.00mA 51% SOC 13260.00mAh
Also, need to incorporate the important charge and discharge limits vs. duration these little packs have, as alluded to here: https://batteryhookup.com/products/bmw- ... 1288381572
That certainly looks like our module but not identical? You can see the 10 sec max power limitation in discharge and charge (re-gen braking). No idea where they would have got this info or how reliable it is but helpful nonetheless. (That was a fantastic price!!) Note the voltages also. I think the lowest voltage is too low?
So, from what I've found on the web, the 330e pack, I think, will do somewhere between 23kW and 32kW continuous power (with cooling), and 58kW to 65kW peak for 10 sec (With lots of cooling!) Some references state 70kW peak, and BMW state the 330e has a 65kW motor, which would match a 70kW battery peak, but that seems quite extreme!
The usable capacity is consistently stated as 5.7kWh. We can work out the usable SOC range and so voltage range from that.
These are all with a very capable, active refrigerant system. Unless that is re-instated, I'm not sure we can access those peak power ratings very often! Also, I'd wonder if the BMW BMS would be modeling the thermal behaviour of the cells vs current in and out and be running a kind of feed forward control to the cooling system. Activating cooling from the sensor measurements may be too slow I'd guess? For a huge EV pack I don't think this is such a big deal but operating these small PHEV packs at peak power for more than a few seconds is going to need care I think?
If anyone has any experience using these packs, has found a good cooling solution and has more reliable data, please share!
I'm thinking of investigating what of the 330e refrigerant system can be re-used with an eAC compressor and my Panda's (eventual) AC system. My first idea of putting water in the pack's refrigerant lines is probably not going to do much, but worth also investigating?
Quick question to Tom, I notice when I remove power to the modules, the CAN comms stop, but none of the data displayed changes from then, its frozen, obviously. I've not had a chance to test yes, but what is your thinking around the status of the BMS when/if that happens? Does it indicate it has lost comms with the modules and suggest zero charge and discharge capability or some other mode change to warn of an unprotected pack? I could see no change in behaviour when I powered down the modules. Maybe I'm worrying too much for a home build!
Thanks.