Making a custom battery pack for MiEV

[Sandrosan]

That's so clean and nice thanks for sharing your Great project bravo

 

[Negue]

Hello. do you still have the useful dimensions from the case? I want to calculate if there is space for cells E63B / E600B (kia hyundai) or from Ioniq 5

 

[kiev]

Doesn't seem likely to fit the modules, but i like the liquid coolant plates.

 

[Negue]

Hope that I can do eazy 1p not like original 3p

 

[Frud]

Hello. do you still have the useful dimensions from the case? I want to calculate if there is space for cells E63B / E600B (kia hyundai) or from Ioniq 5

Dimensions of useful volume 385x650x190 mm. I was considering the option with E600B cells. But it can only be placed in one block in the 44s1p configuration; there is not enough space for 44s2p. The approximate size of the 44s1p E600B block is 385x650x140 mm (5x9) or 385x650x170 mm (4x11).

This is the reason I chose E777 cells.

 

[Negue]

Indeed , I calculate from LEV50 size 171/115/44 and in original position E600B with his plastic case have space for max 44 front / 44 back That means 17kw ( S.H ones have some degradation) Better then actually 10kwh (Soh66%) but I hope more.
Edit 1p configuration

 

[Frud]

I have to disappoint you. Even if you get rid of the factory plastic case of the cell, you will not be able to accommodate more than 44s1p. You will also need to cut off the jumpers at the bottom of the battery case.

 

[MickeyS70]

How do ye plan to connect the CMUs to the pouch cells? Sense wires for the cell voltages are more or less straightforward but the tiny temp sensors are a different story?

 

[Negue]

Yes. Initially I calculate wrong and still needed 40cells to have 2p :/
I don't want to weld (don't have and don't know to) , screws only

 

[Frud]

I plan to use an independent cell temperature measurement system and broadcast the data to the BMU bus. I don’t know yet whether it will be necessary to make an additional CAN bridge CMU-BMU, or whether it will be possible to use only the CAN bridge BMU-ECU.

 

[MickeyS70]

I plan to use an independent cell temperature measurement system and broadcast the data to the BMU bus. I don’t know yet whether it will be necessary to make an additional CAN bridge CMU-BMU, or whether it will be possible to use only the CAN bridge BMU-ECU.

Good question, @piev corrected a faulty temperature reading on the CMU/BMU side, but I gather individual cell temperatures are also available on the BMU/ECU CAN bus…

 

[Frud]

The temperature of individual cells is indeed available on the BMU/ECU CAN bus, but there is a question! Does this data affect the battery heating/cooling control from the ECU, or does the BMU control the battery heating/cooling directly with a separate PID. This remains to be seen. I don't think it will be difficult.

 

[MickeyS70]

The temperature of individual cells is indeed available on the BMU/ECU CAN bus, but there is a question! Does this data affect the battery heating/cooling control from the ECU, or does the BMU control the battery heating/cooling directly with a separate PID. This remains to be seen. I don't think it will be difficult.

There is no battery heating on a triplet, cooling is automatically enabled when CHAdeMON charging is acctivated. Depending on cell temperature either fan alone or together with cool air from AC is used to cool cells.

 

[Frud]

There is no battery heating on a triplet, cooling is automatically activated when CHAdeMON charging is acctivated. Depending on cell temperature either fan alone or together with cool air from AC is used to cool cells.

Do I understand correctly that battery cooling is not used while driving?

 

[MickeyS70]

Do I understand correctly that battery cooling is not used while driving?

Yes, but seemingly there is a ‘hack’ to divert cool air from the AC into the battery pack, not sure how though..

 

[Frud]

Yes, but seemingly there is a ‘hack’ to divert cool air from the AC into the battery pack, not sure how though..

How else can you use cell temperature other than enabling cooling when charging CHAdeMO? Does it affect the movement of the car? Is it acceptable to reduce power/turtle when overheating?

 

[MickeyS70]

Cell temperature is used for various task

- battery capacity correction (not 100%)
- start cooling during rapid charging
- monitoring during AC charge (stops charging when overheating/sensor info is missing)
- supervision while driving (power reduction in case of overheating)
…
@piev anything to add from your experience?

 

[Negue]

AC to cooling cells ? I know about ventilation but natural one.
Can someone give me a link to see it with my oun eyes ?

 

[kiev]

Take a look at the passive cooling thread, here https://myimiev.com/threads/passive-cooling.1515/post-10727

Back in 2015 the forum had a blog feature which i used to post a massive amount of technical findings and information. One of those involved the modification to route A/C cooling air to the pack whenever desired. Unfortunately the blogs were dropped and all those posts are gone. Here is a post with the link to the blog, https://myimiev.com/threads/directing-a-c-air-to-the-main-pack.2681/post-22568