Search found 363 matches

by francisco.shi
Wed, 27 May 2020, 11:37
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 604
Views: 60098

Re: Prelude conversion project - some questions

From the pictures of your pack it looks like the coolant is at the bottom so I assume if there are any leaks it would have to first fill up the box before it got to the terminals which are at the top. From memory I think your cells are epoxied to the bottom coolant plate so the foil should not get w...
by francisco.shi
Wed, 27 May 2020, 07:44
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 604
Views: 60098

Re: Prelude conversion project - some questions

If the cell goes up together with the rest I would expect the cell may be ok. Any chance it was discharged at a different rate than the others? Maybe the bypass is continuously on for that cell? What BMS are you using? Does it have one board per cell or one board does many cells? I would expect the ...
by francisco.shi
Tue, 26 May 2020, 13:45
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 604
Views: 60098

Re: Prelude conversion project - some questions

Any chance it is just the BMS reading incorrectly?
by francisco.shi
Tue, 26 May 2020, 04:55
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 604
Views: 60098

Re: Prelude conversion project - some questions

Can you replace the cell instead of bypassing it?
by francisco.shi
Thu, 21 May 2020, 16:53
Forum: Charging Infrastructure
Topic: How DC chargers work
Replies: 24
Views: 3076

Re: How DC chargers work

The second hand leaf batteries are probably not a bad idea. At 65% of the original capacity when they are removed under warranty to get 160kwh you would need about 10 leaf packs. I am sure there are more than that floating around in Australia. I know of 6 packs that were in a recycling warehouse in ...
by francisco.shi
Thu, 30 Apr 2020, 19:59
Forum: Batteries, charging, management and monitoring
Topic: BMS requirements for energy storage.
Replies: 5
Views: 403

Re: BMS requirements for energy storage.

I am going to use my own BMS. I have the cell top boards working. I can measure voltage and temperature for each cell and can balance the pack. What I need to sort out is the behavior for the main controller. For the car I have control over everything but for the home storage I don't know how much I...
by francisco.shi
Thu, 30 Apr 2020, 05:23
Forum: Batteries, charging, management and monitoring
Topic: BMS requirements for energy storage.
Replies: 5
Views: 403

BMS requirements for energy storage.

I just got my solar panels installed and running. I got a Goodwe hybrid inverter. I am about to connect the battery. The inverter is designed to run on a 48v battery. Maximum voltage is 58v which will be good for 14S NCM pack. My question is what does the BMS need to do other than balancing the batt...
by francisco.shi
Sun, 26 Apr 2020, 16:12
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I have increased the voltage of the battery pack after doing some testing to make sure everything is ok. It has enough volts now to get to about 40kph. It now feels more like a real car. Still only running on one motor and about 75% of peak torque. I should get the next version of the gate drive in ...
by francisco.shi
Sun, 26 Apr 2020, 04:53
Forum: Nissan
Topic: Non OEM Leaf battery upgrade?
Replies: 53
Views: 10834

Re: Non OEM Leaf battery upgrade?

Should have at least put a fan to move the air inside the box.
by francisco.shi
Sun, 26 Apr 2020, 04:48
Forum: Nissan
Topic: Non OEM Leaf battery upgrade?
Replies: 53
Views: 10834

Re: Non OEM Leaf battery upgrade?

The only problem is no cooling.
by francisco.shi
Thu, 23 Apr 2020, 20:55
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

Only one other answer and it was correct. The same as yours. Yes. Soft switching would fix it but it adds a lot of complexity because the current is continuous during the switching cycle so it needs extra components. I did build a power factor corrected PSU front end years ago and it was amazing how...
by francisco.shi
Thu, 23 Apr 2020, 07:05
Forum: Batteries, charging, management and monitoring
Topic: what is peoples thoughts on Active Equalizer Balancer Boards?
Replies: 10
Views: 642

Re: what is peoples thoughts on Active Equalizer Balancer Boards?

My BMS does shift energy from the stronger cells to the weaker cells. So the principle should work. The board has inductors so it has the hardware. So i guess you just have to test it to see if it is good. It is fun to see the lower voltage cells charging and the higher voltage cells discharging wit...
by francisco.shi
Wed, 22 Apr 2020, 06:14
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I guess you did pay attention in class. The answer is spot on. I was a bit worried when I first saw this because I thought two transistors were turning on at the same time. The bus structure and bus capacitor are extremely low impedance so there are a few thousand amps flowing to cause that big a dr...
by francisco.shi
Tue, 21 Apr 2020, 21:20
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I have been doing some further testing on the power stage of the inverter. So far I have been running only one transistor pack so current is limited to 400A. I have been testing at 280A RMS which is about 400A on the peak of the sine wave. I am quite happy with the performance of the gate drive and ...
by francisco.shi
Mon, 20 Apr 2020, 20:28
Forum: Nissan
Topic: Nissan Australia Leaf 1.0 battery replacement
Replies: 45
Views: 6821

Re: Nissan Australia Leaf 1.0 battery replacement

Unfortunately the manufacturer only wants to help themselves.
by francisco.shi
Mon, 20 Apr 2020, 14:16
Forum: Nissan
Topic: Nissan Australia Leaf 1.0 battery replacement
Replies: 45
Views: 6821

Re: Nissan Australia Leaf 1.0 battery replacement

Is there any chance of you replacing the cells? Potentially with higher capacity? Cells are around $300/kWh so a 24kwh battery would be about 7k worth of cells and you would have a new battery. I am also pretty confident some company will come up with an aftermarket replacement. As more and more EVs...
by francisco.shi
Sun, 19 Apr 2020, 19:08
Forum: Nissan
Topic: Nissan Australia Leaf 1.0 battery replacement
Replies: 45
Views: 6821

Re: Nissan Australia Leaf 1.0 battery replacement

How much degradation does your battery have?
by francisco.shi
Tue, 14 Apr 2020, 17:18
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I need to ask my friend but I think it was a 2010.
by francisco.shi
Mon, 13 Apr 2020, 19:51
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I am not going to say anything and see what happens.
The shaft on the power steering module is straight thru. If the module fails the car will still steer.
by francisco.shi
Mon, 13 Apr 2020, 11:44
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 171
Views: 21566

Re: Francisco's Electric Pajero

I have been thinking about the power steering and I didn't want to have a pump running all the time. After talking to a friend he suggested I use an electric power steering module instead. He had one that he used for testing before. It came out of a Toyota Corolla. 20200413_065245.jpg The current dr...
by francisco.shi
Sun, 12 Apr 2020, 18:02
Forum: Batteries, charging, management and monitoring
Topic: 240VAC to 370VDC variable charge rate charger up to 5KW.
Replies: 12
Views: 694

Re: 240VAC to 370VDC variable charge rate charger up to 5KW.

I have been thinking of building the charger.
If I don't need to isolate then I want to build a bidirectional charger so potentially I could get single phase or 3 phase out of the charge plug which would be very convenient as off grid home energy storage.
by francisco.shi
Sun, 12 Apr 2020, 10:39
Forum: Batteries, charging, management and monitoring
Topic: 240VAC to 370VDC variable charge rate charger up to 5KW.
Replies: 12
Views: 694

Re: 240VAC to 370VDC variable charge rate charger up to 5KW.

Do EV onboard battery chargers have isolation between the mains and the battery?
by francisco.shi
Fri, 10 Apr 2020, 20:08
Forum: Electric motors and controllers
Topic: Motor controller to run a Vectrix motor.
Replies: 5
Views: 598

Re: Motor controller to run a Vectrix motor.

I have a 400A 750v IGBT module with gate drive board that I use in my inverter. Would that be of any use?
IGBT block with gate drive board.
IGBT block with gate drive board.
IMG-20200327-WA0010.jpeg (1.24 MiB) Viewed 458 times
by francisco.shi
Fri, 10 Apr 2020, 19:59
Forum: Batteries, charging, management and monitoring
Topic: 240VAC to 370VDC variable charge rate charger up to 5KW.
Replies: 12
Views: 694

Re: 240VAC to 370VDC variable charge rate charger up to 5KW.

A hybrid inverter may be able to do that. You will have to modify the feedback circuit to make the internal bus 370v.