Blog / Batteries
Past few days I've been closing all of the battery boxes and they're attached to the frame as well now. They can't go anywhere anymore, can't get any movement in them at all. To be sure I still added some sealant inbetween the rubber and the boxes so they're completely waterproof. Even though it's all a bit thicker because of the few coats of paint on them it thankfully all still fits pretty good.
Now I could attach the footrests, nerfbar and heelguards again.
Then I tightened the nets in them again and placed the heelguards.
Starting to look like a real quad bike again. This is what it looks like right now.
Meanwhile I still added the extra relay. Enabling and disabling the charge process works perfectly now.
The only thing that's actually left now is aligning the wheels and adding the saddle. Then I can finally make a test ride with it. Think this will happen on Saturday if the weather cooperates a little.
The problem I had yesterday where no power was going to the motor moving forward is already solved. The controller just needed a bit more voltage, the 12V battery was not enough. Today I connected the whole battery pack to the controller and tried again. The motor always gets power now, moving forward and in reverse. For the rest I also had no problems anymore, everything's working perfectly now.
Since there was almost 80V present now I changed the settings of the controller again to see how much power would come from the motor. Tested again with the wheels off the ground and I was very surprised. I only still had 1/8th of the available power but I could already feel really good how strong the motor is. More power I won't test with the wheels off the ground, this will happen during the test ride soon. The coming days I'll be preparing everything for that. So it's going to be very exciting.
It's time for another new update.
The past few days I've been busy connecting all of the battery cells to eachother. It all went well, for extra safety I already isolated all of the tools with some tape. For the rest you just have to stay very focused.
But that's not all yet, I also started on the BMS (Battery Management System).
First I made all of the wires exactly to size.
Then I connected them all to the battery cells and to eachother. Thought it'd be a lot of work but it wasn't all that bad. It was the first time something actually took less time than I expected, usually it always takes longer. They're also connected inbetween the battery boxes, this was actually the hardest since at one part I had to push 4 wires through that wire loom. The size I used actually is for only 3 wires. But it all went fine anyway.
Looks pretty nice too. The green LED's show that they're connected properly and that the battery cell is at the right level.
In the dark it also looks nice with all of those LED's. Just too bad that you won't see any of it anymore once the battery boxes are closed.
I also connected the throttle now. I used 2 resistors for this and one extra wire, these are again for the BMS. These will make sure that there's not much power available anymore once the battery cells drop below a certain level. This way you won't immediately destroy the battery cells while still being able to get off the road safely.
Also placed all of the fuses to be able to test the 12V system. Meanwhile I've already broken one and replaced it, apparently the contactors needed a little more power.
And I can already say that the 12V system is working perfectly. I just had to make a small modification with a relais, for the rest everything seems to be fine. I just have a weird problem where the controller sometimes doesn't give any power the motor after I let it run in reverse and then forward again. Could be that there's just not enough voltage since everything was connected to a 12V battery. Just have to connect the wires to the controller again and then I can try with almost 80V, see if it works better then.
A big update again after a few days of work. I've made cable pass throughs for all of the boxes.
First I completely finished the one for the fuses of the charger and dc-dc converter. Drilled quite a few holes and placed cable glands in them.
This one I could also place on the frame already. Can only connect the cables once everything's on there anyway.
For the next box I didn't use a cable gland, not enough space for it unfortunately. So I just glued a small hose into there. Works pretty good as well.
For the square box I could have placed a cable gland but the space on the inside was very tight then. So I also just glued a small hose into there.
Then the bigger box. Here I was able to use cable glands everywhere.
But the most important is that all of the battery boxes are all done now and finally back in the frame. I just wonder if all of the frames of corner profiles will still fit well since the paint layer is pretty thick but I'll find out soon enough.
Also placed all of the lids on them to see what it'd look like. I'd say it looks pretty nice.
Now I just still have to place those other boxes, then I can start connecting everything. And the top case I still have to get ready as well, probably won't be easy either. But it's really starting to get a move on again.
Today I finished the second box. It's also completely stuffed now with only relays.
First I made a plate again to which I could attach all of the circuit boards. And with all of those spacers inbetween the circuit boards are stacked together as close as possible.
All wires connected again like in the diagram that I made a while ago. There are quite a few.
It all barely fits in the box. With this one I'll also add a cable gland so all of these wires can go outside. And I'll spray it black myself tomorrow. Wasn't really planning on using this one, that's why it wasn't sprayed together with rest of the boxes.
Meanwhile I'm also busy charging all of the batteries one by one to the same level. Takes about 1,5 hour for each battery so it'll still take me a while.
Now I still have to finish 2 more of these kind of boxes, only after that I'll start with the battery boxes.