Search found 225 matches

by francisco.shi
Sat, 05 Oct 2019, 17:55
Forum: Members Machines
Topic: Soyachips’ Electric FZR250
Replies: 50
Views: 2040

Re: Soyachips’ Electric FZR250

I much does the battery pack weigh?
by francisco.shi
Fri, 20 Sep 2019, 05:09
Forum: Batteries, charging, management and monitoring
Topic: E63 LG 63Ah NCM battery group buy
Replies: 32
Views: 1992

Re: E63 LG 63Ah NCM battery group buy

I put an 8x50mm short piece of copper that connects to the tabs on one end and the other side goes to a length of welding cable that goes to the load.
by francisco.shi
Thu, 19 Sep 2019, 04:43
Forum: General EV Discussion
Topic: AC 3 phase motor fee spinning
Replies: 10
Views: 273

Re: AC 3 phase motor fee spinning

If you have an induction motor you do not need to disconnect the motor. As long as there is no power on the stator windings it will freewheel no problems. As for the max speed induction motors are good in that once you run out of volts you can keep increasing the frequency and the motor will keep sp...
by francisco.shi
Wed, 18 Sep 2019, 21:11
Forum: Batteries, charging, management and monitoring
Topic: E63 LG 63Ah NCM battery group buy
Replies: 32
Views: 1992

Re: E63 LG 63Ah NCM battery group buy

The maximum I tried was 2C continuous for 30min. That was about 400A.
I didn't do a higher current because I didn't have a load that could handle it. The pack voltage was 40v.
by francisco.shi
Thu, 12 Sep 2019, 17:35
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

I am thinking more about straight solar inverters with no battery hardware.
So I assume when the solar panels are not generating any electricity would the bus drop until the mains start feeding back in?
by francisco.shi
Thu, 12 Sep 2019, 08:31
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

I have been giving this idea some extra serious though.
Does anyone know much about how the solar inverters work ?
What is the bus voltage to where the solar panels feed to?
Does anyone have a circuit diagram of the power electronics of a solar inverter?
Do all inverters use the same topology?
by francisco.shi
Wed, 04 Sep 2019, 03:58
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

The car connects to the house via the dc charging port. As far as I understand when charging the car connects the battery to the port and the external charger does all the work. As long as the car does not disconnect the battery when it sees power being taken out. You do not need a BMS for the car b...
by francisco.shi
Sun, 01 Sep 2019, 11:51
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

I was thinking more of an off grid system and use the car battery as backup for when it is cloudy for a few days.
You would still need a small storage battery.
by francisco.shi
Sat, 31 Aug 2019, 18:40
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

I have been thinking about how to do this. As you said most solar panel strings would be able to feed the car battery directly. And most solar inverters I assume would have a 400 or so volt bus. So it may be as simple as just connecting the car battery to the internal bus and reprogramming the inver...
by francisco.shi
Sat, 31 Aug 2019, 12:21
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

I read it on a research paper. I am not sure if it was this one. https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.researchgate.net/publication/318816856_The_effect_of_external_compressive_loads_on_the_cycle_lifetime_of_lithium-ion_pouch_cells&ved=2ahUKEwjtnoiJoKzkAhULeCsKHWa-CO0QFjAB...
by francisco.shi
Sat, 31 Aug 2019, 12:13
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

Plan C would be to have two electric cars with 40kwh+ battery each and when supply is too low run off the car battery. When car is getting low you can go to a fast charger and recharge.
If you use say 12kwh/day your car batteries would keep you going for about a week.
by francisco.shi
Fri, 30 Aug 2019, 06:31
Forum: Renewable Energy and Storage (Non-EV)
Topic: Tesla PW2
Replies: 34
Views: 2522

Re: Tesla PW2

Or you could install enough backup and panels to run off grid and tell western power that you are moving and do not want the connection anymore.
It seems it is becoming easier to go off grid. It is just a matter of how much you get for your excess electricity vs how much you pay in connection fees.
by francisco.shi
Tue, 27 Aug 2019, 18:40
Forum: For Sale/Wanted
Topic: car hoist
Replies: 10
Views: 337

Re: car hoist

You can change the wiring from star to delta and will run at the same speed.
And if you put a vfd you can adjust how fast it goes up so you can get very accurate positioning.
So better start working on your explanations.
by francisco.shi
Tue, 27 Aug 2019, 14:43
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 428
Views: 28015

Re: Prelude conversion project - some questions

You are right about the increase in resolution. It is a very long time since I did uni.
The idea of keeping the old measurements was to make a low pass filter. I just not very good at explaining it.
by francisco.shi
Tue, 27 Aug 2019, 13:22
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 428
Views: 28015

Re: Prelude conversion project - some questions

Just a note on the averaging. You can increase the resolution of the ADC by adding the values and keeping a total. For example if you read the ADC 4 times you will be adding 2 bits to the ADC resolution. This is assuming you have some noise in your input which is higher than 1 bit. Then if you divid...
by francisco.shi
Thu, 22 Aug 2019, 06:30
Forum: Batteries, charging, management and monitoring
Topic: Battery cooling academic paper
Replies: 6
Views: 262

Re: Battery cooling academic paper

All these papers and experiments look great but none of them look practical. Either would be too heavy or too big and will not fit in the car.
by francisco.shi
Mon, 19 Aug 2019, 11:52
Forum: For Sale/Wanted
Topic: Bushbus and my gumtree stuff around. Bushbus needs cells
Replies: 16
Views: 467

Re: Bushbus and my gumtree stuff around. Bushbus needs cells

I've thought about it and I think it's as much work as getting my 18650 pack together and I just don't have the time or brain capacity at the moment. I'll keep hoping for some decent lifepo4 like the bus cells or the ones Dan007a got in the end. I think it is much easier than using 18650s. If you w...
by francisco.shi
Sun, 18 Aug 2019, 14:04
Forum: For Sale/Wanted
Topic: Bushbus and my gumtree stuff around. Bushbus needs cells
Replies: 16
Views: 467

Re: Bushbus and my gumtree stuff around. Bushbus needs cells

Here are the details of the cells:
viewtopic.php?f=17&t=5909#p71878

The pouches are A$64 each.
If you read the thread there are some pictures of how to connect them together.
by francisco.shi
Sun, 18 Aug 2019, 11:18
Forum: For Sale/Wanted
Topic: Bushbus and my gumtree stuff around. Bushbus needs cells
Replies: 16
Views: 467

Re: Bushbus and my gumtree stuff around. Bushbus needs cells

I have some LG E63 cells that I can sell if you wouldn't mind using pouch cells.
by francisco.shi
Wed, 14 Aug 2019, 05:53
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

From what I have read up you need around 10psi minimum pressure to keep the cells from expanding during operation. That is about 270kg per pouch. I do not think 25kg extra will make much difference.
by francisco.shi
Tue, 13 Aug 2019, 12:10
Forum: Members Machines
Topic: Brendon_m Moke
Replies: 141
Views: 10078

Re: Brendon_m Moke

Put a Tesla drive train on front and back and it will upset any petrolhead on the road.
by francisco.shi
Tue, 13 Aug 2019, 07:29
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

I think you could get 6 blocks of 30 instead of 6 blocks of 25. As for being able to get to any contact with no fuss it is a little difficult. One of the good things about having the tabs on opposite sides of the cells is that you use very little space for the interconnects and they can be put insid...
by francisco.shi
Tue, 13 Aug 2019, 06:45
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

For the back box could you rotate the cells so they are flat on the 310mm? That would fit the 137mm perfectly. Then either put more cells in the back box and less at the front or make the back box smaller. I would also keep the cells all together. The gap in the middle will make it really messy to g...
by francisco.shi
Tue, 13 Aug 2019, 06:41
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

This is how I would do it.
1565649376595133065444.jpg
1565649376595133065444.jpg (743.22 KiB) Viewed 466 times
The blocks in the middle should be strong enough they will stay flat. You could do away with the end springs if you put a thick enough bit of aluminium but I think the spring is easier and uses less space.
by francisco.shi
Tue, 13 Aug 2019, 03:43
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 223
Views: 38506

Re: 4Springs' Brumby

You do not need the middle spring. You can just put aluminium spacers in the middle and two long bolts that hold the whole lot. The spacers would be thick enough that you do not need the spring in the middle. You only need the two end springs. The spring is steel and will not conduct very well. The ...