My Project Lithium Battery Caught Fire

The whole point of the Signal Soother was to prevent error codes being read by the Battery ECU which were real and present in the Modules... that is how it came into existence and why it was implemented. This is what you need to fundamentally understand. The Battery ECU would detect errors of Internal Resistance. I experienced this during beta testing. Below is a text I sent to Jack a few weeks ago.



The Signal Soother was created to stop exactly what you said it should not stop... that is why the logic of the device is so flawed. It stops communication of errors that are real and occuring and was it's entire purpose. A signal soother wouldn't have been needed if there were no errors.

Yes... Jack did do exactly what you said shouldn't be done... the reason was he got it in his head that the error codes were glitches when they were not.

I think this is primarily because the Battery ECU does not transmit Internal Resistance readings as viewable parameter via OBDII until the Battery is above 70°F... but is still actively measuring Resistance in the background even though it's not viewable in Dr. Prius. So the Battery Modules were experiencing increased resistance due to an underlying flaw in the Module and the Battery ECU was detecting it correctly... but internal resistance would not show the accurate # as viewable parameter in Dr. Prius until 70°F was hit for pack temperature... even though it would still record it accurately in the background. I tried explaining this to him at the time... but he wouldn't listen:

You'll need to clarify... there are not reduced number of active sense lines with Project Lithium... sure OEM NiMh had 28 modules and Project Lithium had 14... but 2 Nimh Modules are the equivalent of a Project Lithium Module. There's an internal bus bar that connects the Lithium Module to itself.

NiMh there's 1 voltage sense wire for every 2 Modules with a total of 28 modules...

Project Lithium There's 1 voltage sense wire for every 1 module with a total of 14 modules.

1 Project Lithium Module is the equivalent of 2 NiMh Module.

 

You're making it more complex than it really is. The Engine status is not very important... Pedal Angle and speed are the primary factors that controls what system outputs the required amount of power. Software is written for when at certain speeds and pedal angles to demand certain amounts of power from each component (Hybrid Battery or Engine).

The Primary factor that effects power output or input from the Hybrid Battery or Engine besides speed and pedal angle is the temperature of the hybrid Battery itself. The MAX Charge and Discharge parameters in Dr. Prius are the power output parameters allowed. These will both fluctuate when the Hybrid Battery is outside it's optimal temperature range of 77-104°F. The more temps go to the extreme in either direction... the less power output will be allowed.

For example my Gen 2 Prius at 77°F Outputs 28 hp and inputs 33.5hp for regenerative braking.

At 0°F... it's less than 5hp for both. At this temperature the engine will basically bear the sole burden of power delivering.

At 32°F.... it's between 12-15hp for both. Watch here to see what I mean and notice how the maximum Hybrid Battery Ouput allowed (the orange line) is higher by the end of the video due to increased temp of the Hybrid Battery:

This video here is not as good but see how the orange line increases as Hybrid Battery temperature increases as well?:

The Voltage and Resistance parameters are there to calculate State of Charge and that's basically it... Adjusting the voltage readings using a signal will make little difference and is silly and dangerous... You want to be recieving raw Voltage and Internal Resistance readings of the battery at all times. Any device that's added to alter signals makes the whole system more complex than it should be.

Ideally the Battery that's installed should be able to tolerate the voltage and temperature range of the OEM NiMh Battery and balance the cells properly. That's it. Then throw in some increased capacity to the Battery design. The Hybrid Control ECU will then regulate charge in and out based off of it's predetermined NiMh software tolerance programming according primarily to voltage... and you should have no issues in an ideal scenario if the Hybrid Battery is well built. Simple is better unless you're going to re-write the cote Hybrid Control ECU programming to accommodate different voltage range and spec of a different Hybrid Battery. But that will be so complex of an undertaking it's not worth it.

 

Begging the question. Keep in mind that maybe you have seen more of the Signal Soother up close than I have. All I have seen is one photo from which I can tell it's inserted between the sense wire harness and the ECU. What's inside the 'soother' I have to regard as a black box until I see more.

What could be inside the black box? Any number of things.

It could leave the middle twelve of the sense wires unconnected, and be feeding the battery ECU from a multi-tap voltage divider between the outer two.

It could have all the sense wires connected to a voltage divider with much lower impedance than the ECU inputs. Currents would then flow in the individual wires when the block voltages were unequal, and those currents would be higher than anything flowing to the ECU.

Those are just two possibilities, and without yet considering any possible active components in the 'soother'.

Teardown photos or videos or a schematic would reveal what's going on. Guessing requires too many assumptions.

If anybody has a Signal Soother they'd be willing to send me, I'd be happy to examine it myself.

 

well phooey

it didn't go to the fire department with the other stuff?

 

so, the reason I ask is the ECUs in these cars are smarter than we give them credit for. I cant divulge all the information yet but, when I say the ECU will learn the new and adjust to function properly... its really smart...

 

Say, if anyone else has one of these batteries and either has it go bad, or is considering taking it out of service after reading this thread, I'd be interested in the mysterious Signal Soother.

 

@sworzeh Do you have pictures of the burned out modules? Apparently it was safe enough to remove from the car and no other electronics was damage. Did any of the modules swell or visibly burned out? Or was it just smoked that you saw? Did you replace individual modules to the new OEM modules or did you replace the entire pack? Just curious to know how LFP handled this situation. LFP is going to become more industry wide by 2025.

 

If someone wants to send me a Signal Soother, I'll reverse engineer the entire schematic and then film a video showing exactly what it's doing. IMO Jack should be transparent about this, but I will do so in his absence. @jacktheripper, you could save me some time by just sending me the schematic... or you can just wait for me to get one and do it myself.

I agree with the suggestion that there is theoretically a safe way to "Soothe the Signals", but I'm gonna go out on a limb and guess the Signal Soother isn't that.

 

Thanks. Looks like a lot of heat but no runaway fire and contained to one module. I'm surprised even the foam was not affected. Glad to see you and your car is OK and driving again. Jack needs to make sure Toyota safety systems can detect and alert drivers of thermal events like this. The cause should really be identified and the right actions taken. I'm also surprised none of the early beta testers encountered this.

 

I can take closer pictures of the soother later for closer inspection.

I have been a beta tester for these lithium packs since version one.

I have never had a fire and I have overcharged, discharged and shorted these packs.

I now use the soother to help in cold weather and it works.

Tested a soother with a blade with high voltage on purpose and the blade swelled up and hybrid system threw a code when this happened.

Jack said why this fire happened in post 6

Because of this issue there will be even stronger quality control with these lithium packs.

I would have sent the burnt pack with soother back to Jack for investigation.

The customer has been refunded completely and was given and offered replacements.

The packs are safe as long as everything is all connected securely.

 

He can't possibly know if this is true or not... this is an educated guess, a PR move, and potential obfuscation of the truth. Don't you think it's strange how the battery ECU is registering error codes like P0A80 and the solution to stop it is a Signal Soother? Wouldn't it have made sense for Jack to validate that the circuit board was connected before sending out the Signal Soother if there had been a previous #10 special blade board that was disconnected? Why didn't he do that instead of send a signal soother 1st? Link to post #6.

In the Reddit Post he says there was a previous incident before @sworzeh's failure.

Either way this validates exactly why a Signal Soother in any circumstance is a dangerous idea. @sworzeh was recieving P0A80... and a signal soother was installed to prevent it... when all the while the circuit board was disconnected and the Lithium Module wasn't balancing properly. See how the entire concept of a "Signal Soother" is foundationally asking for more problems?

If you need to add a device that alters signals in anyway from the Hybrid Battery pack... and blinds the Battery ECU even if slightly... the whole concept is extremely flawed at best... dangerous at worse.

Would you be willing to post a video of this happening? Maybe charge the blade connected to the Prius, signal soother installed, and Battery cover removed with a multi-meter measuring the data at the specific blade you're over-charging? and then do a screen recording simultaneously in Dr. Prius with the Prius only in Ignition On Mode and sink up the video later? This would go far to prove what you say is true and will validate or invalidate some of the concerns I'm having.

I made a video doing something similar when my 1st pack I bought failed in 3 days fall 2022. I did the test in READY mode instead of Ignition On Mode like you'd need to do @AzusaPrius :

 

I really wish I could've gotten those cells from you... I think a lot could've been learned from them.

 

but wait... this is your educated guess as well as you don't know what he truly knows.
it grinds my gears when people type their assumptions as if they are facts when in reality, most times their words just muddy the waters and unintentionally cause fresh minds to have judgment based on words someone just typed because that's what they felt like is the reality.

come on man! I thought you were working with him? Keep the passion just try to keep emotions and assumptions out of your words because some people cant read between the lines like others...

 

Also, Here is some useful Toyota Manual info describing the functions of the Battery ECU and other ECUs:

 

I do not have video of the test but I do have plenty of pictures and you can see the changes and outcome.

I can create a thread with that information.

Be on the look out...

 

Okay... explain how he could possibly know the cause of failure?

If the Battery module failed and melted... and he hasn't recieved the pack... what would lead you to believe he can truly know the cause was a disconnected circuit board... because during my beta testing with V2.5 I recieved similar failure codes exactly like @sworzeh was getting during the cold and that was the main reason Jack created a signal soother... and my circuit board wasn't disconnected.

I believed at the time there was a serious defect in the modules and creating a signal soother to solve it was the wrong path forward... which is why I ended my Beta Testing a week after the above photo... because I feared the signal soother would create the exact circumstance we have seen in @sworzeh's post. Jack has recalled the signal soother since I messaged him about it yesterday.

I will go back to the fact that even if the circuit board was disconnected and Jack is 100% right in that regard... it shows that fixing errors being read by the Battery ECU with a Signal Soother is a disaster waiting to happen... as we've seen evidence of in this post. The Signal Soother is what caused the fire.

It's not an educated guess... it's a factual statement that I made. He can't know for sure that a disconnected circuit board caused the failure... because there's no mechanism by which he possibly can prove that if he's never verified at any point @sworzeh's circuit board was actually disconnected... as I explained in my Reddit Comment.

 

It would be infinitely more useful to make the video like I made above... that way we can compare realtime the differences in voltage between modules when one is bad from the raw signals to what the Battery ECU is detecting after the signal soother does it's "soothing".

Ideally you'd have to put a multimeter on every blade while this is happening and it's charging and discharging in the pack and do this Test in READY Mode as well... but I'd settle for data on one blade.

 

I'm not working with him... I'm going to explain things exactly as I see them in a diplomatic way. You can read my most recent message to Jack here and how I'm going to conduct myself going forward.

Nothing I'm saying is emotional. It is factual and based in logic. You're welcome to pick apart what I'm saying that is infactual on a logical level. Be specific as to how Jack can know the Project Lithium Module failed due to a disconnected Circuit Board rather than some other error if he never verified @sworzeh's pack had a disconnected Circuit Board. Please be specific.

And again... the failure and fire is not a direct result of a disconnected Circuit board... It is a direct result of the Signal soother altering Voltage and Internal Resistance readings preventing the failure from being seen in the 1st place which prevented the Hybrid System from taking the necessary protective actions. The fire 99% would have likely been prevented if the signal soother was never installed.

Everything I say is an attempt to stand on a foundation of truth and principal, rather than obfuscation.