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Discussion Starter #1
Hi every body!
I always thought that during driving and charging battery cooling is the most important thing for safety and reliability.

I'm reading that Audi and Tesla now preheat the battery before arriving to a supercharger.. I was wondering why the pre heat them, I thought fast charging will increase battery temperature and for this reason battery must be cooled down with active cooling buy fans and a/c cooling...

I'm confused...
 

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Doing so ensures the battery is at an optimal temperature, which might require additional cooling or heating dependent on ambient and use related battery temperatures.
 

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Battery charging, and discharging, involves a chemical reaction within the cells. Within reasonable limits, additional thermal energy aids most chemical reactions and makes for faster and more efficient ion and electron transfer.
 

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Discussion Starter #4
It would be Interesting to see those parameters... It maybe be possibile to control that in a diy project
 

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Tesla: Our cooling system engages to try and keep the temperature of the cells below 35° C at all times and the lifetime average temperature at or below 25° C.

Myself I like this graph to understand the matter:


In my project I am adding DC fastcharging and both passive & active cooling and heating capability for the batteries. Once I finish I will use data from the BMS to develop cooling and heating strategies.
 

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Discussion Starter #6
Tesla: Our cooling system engages to try and keep the temperature of the cells below 35° C at all times and the lifetime average temperature at or below 25° C.

Myself I like this graph to understand the matter:


In my project I am adding DC fastcharging and both passive & active cooling and heating capability for the batteries. Once I finish I will use data from the BMS to develop cooling and heating strategies.
hi where can i follow your build?

i'm trying to understand how should i make a fast charge with chademo works and i would love to read any info on that... are you using a custom bms?

i want to run the classic big drive unit tesla with a single chevy volt battery (for the first step) and i can't understand if i need a full bms or the oem can handle such a protocol.... damien mcguire looks like is running oem bms but still is make the chademo charging...
 

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My project blog is https://www.oudevolvo.nl/english/
Detailed (more or less daily) updates in English can be found in Instagram https://www.instagram.com/oudevolvo/

The CHAdeMO socket is in place (see blogpost in Dutch, unfortunately not available in English)

CHAdeMO controller I'm not sure about yet, but it will come to a landing soon and then I will write a blogpost about it. I'm using the Lithium Balance n-BMS.

The CHAdeMO controller and BMS need to communicate over CAN exchanging all kind of information such as voltages, currents, DC SoC target, etcetera.
The CHAdeMO controller does the CAN handshake with the DC charger on one bus and also communicates with the BMS. Since the timing with the DC charger is quite specific, the BMS needs to provide the required information within a certain timeframe.
 
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