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This tool can not read BMS.
if you need help, send me the unit, I can help you with clear error.
price is 500$
WhatsApp +380931130000
GoSmart Service, am I understanding you correctly that if we get a "bricked" battery, we can simply remove the battery from the vehicle, re-charge the individual cells, re-install the battery in the car.

Then remove the BMS, send it to you for clearing of the error, re-install the BMS back into the car after we get it back from you, and then everything is working again?
 

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GoSmart.com.ua shows 3 BMS boards atop a smart_batt. Is there a lower level with 3 more?
I suspect he means we should ship the whole batt to Kiev.
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As usual it depends :)
If you have a dead battery with cells which are dead and you could not recovery Thema Athen the Ukraine friends need the whole battery and can repair it. If only the P18051C is the failure left, they can help you by flashing the BMS again and reset the protected failure code Areal. This will also delete the P18051C failure code. For this you only need to send them you BMS and your bucks :)
So everything could be solved somehow. It is just a mature of time and money (or knowledge).
 

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GoSmart.com.ua shows 3 BMS boards atop a smart_batt. Is there a lower level with 3 more?
I suspect he means we should ship the whole batt to Kiev.
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Those three boards are the "supervisory boards". The BMS is a small module near the left rear corner of the battery pack (not visible in the photo). Disconnect the connector to the current sensor of the bus bar near it before removing.
 

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My 12v batt died and the HV battery bricked itself (yet another smart car COVID 19 shutdown victim). I removed the battery and started charging with a lab supply but I noticed one cell was a dead short (5mV while all other cells were 1.5V)

Question: does the 451 HV BMS have the capability to shunt around a bad cell or is the pack ruined if one cell goes bad?

thanks!
m-
 

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My 12v batt died and the HV battery bricked itself (yet another smart car COVID 19 shutdown victim). I removed the battery and started charging with a lab supply but I noticed one cell was a dead short (5mV while all other cells were 1.5V)

Question: does the 451 HV BMS have the capability to shunt around a bad cell or is the pack ruined if one cell goes bad?

thanks!
m-
There is no possibility of bridging a bad cell. The chain is as strong as the weakest link. If one link is bad it have to be replaced.
But the 15mV voltage itself is not the final verdict. You should try to charge a weak cell as soon as possible, (as well as all others) with a small current up to a voltage of 3V+ per cell, and over that voltage the charging current can increase. If the voltage of all cells is stable for a few days, that could be a good sign. If the voltage drops, the cell is permanently damaged.
 

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There is no possibility of bridging a bad cell. The chain is as strong as the weakest link. If one link is bad it have to be replaced.
But the 15mV voltage itself is not the final verdict. You should try to charge a weak cell as soon as possible, (as well as all others) with a small current up to a voltage of 3V+ per cell, and over that voltage the charging current can increase. If the voltage of all cells is stable for a few days, that could be a good sign. If the voltage drops, the cell is permanently damaged.
I charged the pack for about 6 hours with 50mA constant current. all the good cells started at about 300mV and ending at about 1.2V average. The "Bad" Cell started at 5mV and ended the charge at 5mV. The next day, (i did not charge over night) all cell roughly held there voltage and the bad cell was still 5mV. That cell is pretty much a short circuit

I'm thinking the pack is toast.

It would be interesting to try are replace just this one battery assemble as it looks like there are 3 identical assembles in the battery pack but this whole think is starting to be a bit of a goat-rope. I guess MB thinks we have lots of time to kill trying to fix their poor design decisions..
m-
 

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We could sure use info on the size of these prismatic cells, then compare to readily available cells that might fit inside the power pack. It seems unlikely that Daimler would build these packs with unique cells, rather I suspect that they might use the same or similar cells as other EV manufacturers.

We can disassemble a Leaf can which contains several pouch cells and then if they fit, substitute in the Smart pack to fully populate all 91 (or 93 in the 453) cells. Likewise Volt/Spark/Bolt pouches.
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All indication is that Daimler built a proprietary HV battery - it’s what happens when the “smartest man in the room” drinks ALL the Kool-Aid?

The lithium-ion battery in the smart fortwo electric drive was developed by Deutsche
ACCUmotive, a Daimler AG subsidiary specially set up to develop and produce batteries.
The lithium-ion battery consists of 93 single cells and offers numerous advantages:..."

You probably will not be able to buy them, since they will not be commercially available. Unfortunately, this is often the case for BEV cells.

The lithium-ion battery in the smart fortwo electric drive was developed by Deutsche
ACCUmotive, a Daimler AG subsidiary specially set up to develop and produce batteries.
The lithium-ion battery consists of 93 single cells and offers numerous advantages:..."

You probably will not be able to buy them, since they will not be commercially available. Unfortunately, this is often the case for BEV cells.

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.smart.com/content/dam/smart/EN/PDF/smart_electric_drive_Broschuere_en_INT.indd.pdf&ved=2ahUKEwiV-JPZ3afiAhUdxMQBHfasBAQQFjALegQIAhAB&usg=AOvVaw1dYc5pbyAvKsbNr0VPBU4g
 

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I charged the pack for about 6 hours with 50mA constant current. all the good cells started at about 300mV and ending at about 1.2V average. The "Bad" Cell started at 5mV and ended the charge at 5mV. The next day, (i did not charge over night) all cell roughly held there voltage and the bad cell was still 5mV. That cell is pretty much a short circuit

I'm thinking the pack is toast.

It would be interesting to try are replace just this one battery assemble as it looks like there are 3 identical assembles in the battery pack but this whole think is starting to be a bit of a goat-rope. I guess MB thinks we have lots of time to kill trying to fix their poor design decisions..
m-
Charging must be continuous up to 3V. You have to use a charger you trust and leave it on for a couple of days until a + 3V / cell is reached. If the voltage drops even then, further attempts are a waste of time.
 

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Can anyone comment on whether the 3 "modules" (within the battery pack) and their "supervisory boards" are interchangeable, can be swapped around if reprogrammed, or should not be messed with ? They seem identical and bus bars easily removed.

there are videos on youtube of people replacing or re-purposing these (li-tec pouch type) cells, however for in car use, I'd probably be more comfortable replacing the whole "module"
 

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Hi,

I have a
Smart fortwo electric drive 35 kW Electric drive Standard
and i need to replace electrical battery - can you help me with a link from where i can buy it, even an update one.

Thank you!
 

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How do you know it is good?

I can see modules

  • N47-5 (ESP control unit)
  • N2/7 (Restraint systems control unit)
  • N15/5 (Electronic selector lever module control unit)

So OBD CAN bus is working. Hardware is working. Other modules should be accessible if sofware is OK. I think so?
 
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