How to wire up a (dis)charge plug for the HV battery?

There must be several explanations with pics/vids showing this, but I cannot find them...

From my memory, there is a relay half way through the battery, so I assume it s not just wiring up two wires and a fuse? I have not seen the inside of a battery in real life, so want to be prepaired.

I want to do some battery maintenance (270000km/170kmiles). I have a charger (1000V 500mA) and 230V bulbs should do for the discharging.

 

Did it today. Must have been 5 hour work. Am I just slow?

Advice for anyone planning this: DON'T SIT ON THE HYBRID BATTERY. It deformed slightly but permanently under my weight (due to lock-down it went from 95 to 100kg again... (220lbs?))

I only put in a pair of wires on the two HV wires, fused it with a 5A fuse very close to where I connected the wires (so blowing it means I have to open it all up again, so I had better be very careful...) and put a XLR-plug into the plastic trim in the boot to connect it up. I found this better than leaving a plug lying around, since I always have lots of stuff in my boot. Not sure if drilling into the plastic was wise, but no turning back now!

While using the "hybridautomotive" guide, I ran into the part about the fan. I don't have the harnass (so some of the 5 hours was used finding the correct wires, ringterminals, XLR-plug, fuse-holder and soldering it all together). What does that thing do? The box that hooks up to the fan? Simply run the fan full tilt while the charger is connected? I have my own charger (not a 'hybridautomotive' but an adjustable CV/CC 1000VDC 500mA powersupply) and adding a seperate 12V powersupply to run the fans is not a huge problem, but knowing if I can just put 12V on the connector or if I have to separate it and (dpdt) switch between the wires from the car and my own powersupply would be nice to know.

 

I removed the fan completely to clean it. It wasn't that dusty (278000km/170k miles), cleaned it with a toothbrush and compressed air, but couldn't get all dust from the fins/blades of the fan. Motor is 12V so while it probably IS PWM (Pulse Width Modulation), just putting straight 12V on it should be no problem.

PWM is a method of lowering the average voltage an LED or a fan or whatever is supplied with it. It is much as a dimmer switch with a lightbulb, but with a DC voltage. If the 12V is switched ON for 1 second and then switched OFF for 9 seconds, the average voltage was 1.2 volt during those 10 seconds. Switch it ON for 5 seconds and OFF for 5 seconds, the average voltage was 6 volts during those 10 seconds.
Obviously it will simply start up during these 5 second and stop accelerating once the 5 seconds are over and probably be stopped before we reach second 10 (mine had quite some resistance). But now change this five seconds to 5 millisecond. Now the accelerating will be only during these 5 milliseconds and then it will decelerate during 5 milliseconds. But the switching ON and OFF will be so fast it never is long enough to accelerate to maximum RPM but also never long enough to come to a full stop. So after a few seconds, there is an equilibrium between the acceleration and the deceleration which results in the same speed as running it with 6 volts.

BTW, I could only properly access the car through the boot as it was parked between two other cars. I like to think that this also slowed me down a bit


The fuse is a standard glass fuse as I thought that was a good fuse for DC. I considered an autmomatic 10A fuse of a car fuse, but neither are suited for 250V DC. In these glass fuses, the 5A slowblow was the biggest I had. I do have some (sand filled) 16A versions in a homebuild powersupply that I no longer use that I could have pillaged, but 16A is fairly big for my wiring (standard 230V double insulated, I think 1mm^2, but might only be 0.75mm^2).
I only have 105W 230V lightbulbs (and two sockets, so only 2A current draw at max), I could wire up a 300W filament thingy, but it gets so bloody hot that I don't want that in my car. But good to know about the inrush current. I hope the fact it is a T (stands for Träge, German for slowblow, and F is from the German "Flink", not Fast even though Flink and Fast mean the same...) means that it won't blow from my limited inrush current.

 

Bedankt Dolj! I already have a 40W halogen bulb. (the 105W is also a small halogen bulb with a large glass bulb around it, the normal 100W bulbs were banned a few years back).

I found a flaw in my plan: the battery prongs in the plug cannot be touched, but when I want to charge it, I will need a male plug attached to my 250 volt charger...

I want to add this thing to measure the amount of power taken out of the battery.

I have a 33V 3A version that can easily be converted to measure 330V (I wrote about that in another thread and hopefully 3A should be enough, that's 600-700W of discharging...). When trying to figure out how to use this both during charging and discharging, I ran into the problem with one way or another ending up with a male plug with 250V on the touchable pins...

So I think I will convert it all to Speakon connectors. They were designed for professional audio like they e.g. use in rockconcerts. It has 4 contacts, each rated at 30A, but I will only use 2. Nicest thing about them is that both the male plug and the female chassis part have contacts that cannot be touched.


One other thing I thought of is that the connection to the 200V Prius battery I made can easily be used for a laptop power supply
They mostly work from 100V through to 250V AC. But as long as it is a SWITCHING powersupply, the first thing such a powersupply does, is rectify the AC voltage to a DC voltage. So it then works on (rectified 100V AC = ) 140V DC to (rectified 250V AC=) 350V DC on its main 400V capacitor. So feeding it with 200V DC (or even 260V while braking), which simply passes through the rectifier and thus fills the same 400V capacitor, would work perfectly.

But anyone trying this: do this at your own risk. If there is anything in the circuitry needing an AC voltage, you might be blowing something up. (I doubt it, but I'm not going to be held accountable for you burning your car down...)