B40 fault B8 system fault

[new-brammo-guy]

If the humidity sensor (%) is our best measurement of the leaking problem, then the problem only exists in the lower modules (5, 6, 7) where we see abnormally high humidity. The humidity in the upper modules seems stable and fine. The fact that you can no longer buy a replacement lower modules indicate they may have failed the most.

What are the differences between the upper modules (1, 2, 3, 4) and the lower modules (5, 6, 7)?

-lower modules are upside down
-3 modules in lower and 4 in upper
-Any other differences? Any components that could leak in the lower that aren't in the upper?

Case I: The moisture was internal to the battery module:
I'm wondering if the upside down orientation caused the problems. Temperature fluctuations could have contributed too over time - high pressure to lower pressure squeezing on the cell while it hung upside down -> fluids slowly dripped out the cell tabs or some other seal.

Case II: The moisture was external to the battery module but crept in through an opening:
Is there any unsealed opening in the lower modules? I'm not convinced yet that water was getting into the modules from the outside. Both the upper and lower modules have the Molex connector (some theorized it came in there). And I never rode my bike on wet pavement - it's super-super clean and dry.

[EV promise]

Hi Korbin, in IMG_4011.jpg has the cell split open and spilled the electrolyte please?
Also does U38 to the left of U14 have any markings on it please. 1046 or 1047 perhaps. Would make sense to measure temperature and humidity next to each other. Thanks.

[new-brammo-guy]

Is the "cell temperature" measured with a sensor on the PCB with close proximity or contact with the cell tabs? If so, they should be fairly lined up across the different cell tabs.

[EV promise]

To me it looks like the cell temp is measured on the heater plates and is separate from the pcb temperature and humidity sensors as there are values for all these in the data. We need an electronics engineering to look over the boards and battery to understand things better. I think the F506 microcontroller does the monitoring (all it's common uses are just that) and the other one, whatever it is looks after battery usage.

[new-brammo-guy]

I have access to electrical engineers. Anyone have the PCB layout diagrams?

[Korbin Dallas]

Hi Korbin, in IMG_4011.jpg has the cell split open and spilled the electrolyte please?
Also does U38 to the left of U14 have any markings on it please. 1046 or 1047 perhaps. Would make sense to measure temperature and humidity next to each other. Thanks.

I could not tell that any of the cells had split open . In the picture you can see the row i took the cells out of and it exposes the cell heater. On the cell heater is sticky tape and i damaged it trying to get the cells out. The picture looks as though something is on the cell heater but it is not. The gold item at the top ( right side of pic) is the connection for the cell heater. On the back side of that is the temp probe. Both connect at the circuit board on the same plug. Resistance of the heater shows similar to all the other heater connection. After applying heat with a heat gun resistance decreases. I only had time to check one. I will check the u38 and U14 this weekend.

[Korbin Dallas]

Hmmm?

https://www.pneumaticplus.com/arrow-pneumatics-dfd-10-1-4-miniature-in-line-desiccant-dryer-2-pack/

[Korbin Dallas]

Also does U38 to the left of U14 have any markings on it please. 1046 or 1047 perhaps. Would make sense to measure temperature and humidity next to each other. Thanks.

It looks like either 98PN or 48PN on the top of u38

[Korbin Dallas]

after scraping off crap

[EV promise]

Great picture. My thoughts are you'll have to replace the two damaged heater sockets as they've lost some of the pins.
I'd expect it to come back to life as the heaters are used to balance the cells and have the temperature sensors also vital to operation. Other damage looks superficial. Once your able to hook up the software as Lennon did things will become clearer. Hopefully the module will pass and the B40 code will clear.

[KaFr]

The last photos of module 5 show the mechanism of how the board was damaged:

A large amount of chemical fluid was leaking from the cells in the middle of the module 5, most in the right part (viewed from above). Then it started dripping from the edge of the metal plate that connects the contacts, unfortunately right into where the heater + temperature sensor connector is soldered. Due to the large amount of liquid and the long exposure time, it destroyed the soldering of the two connectors on the board. Then it flowed to the edge of the board, mostly diagonally, because the bike was on the side stand for a long time. Then the rest of the liquid dripped from the edge of the board onto the lid of the module and flowed into its lowest part.

Unfortunately, this is the result of a bad design, where the bottom module is turned by the board with the electronics in the bottom part and it is not protected in any way against the flowing liquid escaping from the cells.

It is also interesting that the most damaged board is in all known cases of failure of the heater in module 5. Therefore, the liquid leakage is the largest in module 5. I assume that a possible system error during the assembly of module 5. For example, connecting the cells of module 5 through a metal plate to the main pole of the battery could be inaccurate and there could be a lot of pressure on these cells.

I confirm that even in my case the humidity is greatest in module 5.

What do you think about it?

[Korbin Dallas]

possible route for water or humidity into the case.
The blue dot on the outside is just a sticker covering the vent holes
Inside is also a sticker but has a different feel to it
picture show case as it would be installed in bike
add tilt to the left for side stand
This is also why you have chemical smell if something is happening inside

[KaFr]

Hmmm?

https://www.pneumaticplus.com/arrow-pneumatics-dfd-10-1-4-miniature-in-line-desiccant-dryer-2-pack/

I think this filter is a good solution if you want to reduce the humidity inside the battery pack without disassembling it as follows:
- unscrew the sight glasses on both sides of the package
- screw the filter on the front side of the package
- screw the hose connected to the compressor to the filter
- with compressed air, inject guaranteed clean air into the package and it pushes the moist chemical air out through the second hole

Personally, I would rather use the opposite method, where I would suck the dirty chemical moist air out of the module, for example using a vacuum cleaner. In this case, this type of filter is not necessary. All you have to do is place a particulate filter on the inlet opening and the air in the outdoor environment will have significantly lower humidity than the air in the package.

I'm going to try this procedure as soon as possible to see if it has any significant effect for reducing humidity, but unfortunately we've had a lot of rainy weather for the last week.

[KaFr]

possible route for water or humidity into the case.
The blue dot on the outside is just a sticker covering the vent holes
Inside is also a sticker but has a different feel to it
picture show case as it would be installed in bike
add tilt to the left for side stand
This is also why you have chemical smell if something is happening inside

Interesting finding. Why did the Brammo designers seal the air vent? Did they think that chemistry could not leak from the cells? I think that's the wrong conclusion. Bag cells can never be perfectly tight. And increased humidity also promotes corrosion processes!

I'm thinking of drilling a hole in the sight glasses, which are only accessible after removing the covers. I would stick a tube with a closable end into this opening and, as a precaution, I would, for example, vacuum out the moist air once a month. Although this would not prevent the leakage of chemical liquid from the cells, I think that I would significantly slow down the corrosion process that occurs on the metal plates connecting the contacts. The chemical liquid would dry out relatively quickly.

Off topic:
My electric car Renault Fluence Z.E. from 2012 uses first-generation Nissan Leaf modules. There are also pouch cells inside the modules. I also sometimes smell a chemical smell inside the car, especially when the battery is very hot and its cooling starts. This is done in such a way that outside air is sucked into the battery pack by a fan and then exhausted into the interior of the vehicle. These cells have a lot of SoH degradation, about 4% per year. But luckily the electronics are outside the package so they are protected from chemical fumes or liquid.

[Korbin Dallas]

I like your idea about a closed system with the air dryer. I never thought about that. I was just looking for something to reduce water vapor. We use Nitrogen in aircraft tires to reduce the water accumulation. Could we pump nitrogen thru the sight glass?

Back to my corrosion question from earlier....Are the cells actually leaking? Or is it just a chemical reaction to water ? Also if this is vented to the atmosphere then there is continuing humidity being added which would increase the condensation during the heating and cooling of the battery and over time would form droplets most likely in the same places on the interior of the battery. Then dripping on to or running over the cell connections and increasing the corrosion and chemical reaction leading to the damage to the circuit boards in specific locations.  We really need another  battery disassembled to compare damage areas. And in the mean time come up with a solution to reduce humidity levels