The more electric goes up, the faster the break even comes round. ;)


Hopefully. My SWMBO isn't so fussy about such things, although for me, the panels would be on the back of my house for maximum sun hours.


One of my ideas was to run another independent ring main, which runs off solar/batteries.
If it's used to power long term, lower power items like fridges, freezers, TV, computers, and so on, the savings can be large, especially if you have enough energy to power a tumble dryer. The trick is maximise your solar storage, and minimise your mains supply, but you know this already. ;)
That's what I did. ;) I put sockets in my office and around the house that were wind powered when the batteries were charged and ring mains powered when the batteries were low. The batteries I had were in poor condition when I got them (for free) and the best my wind turbine could manage was 1.2kW on a windy day, most of the time I got a couple of hundred watts at best. It was only when I had the wind turbine up that I realised our area isn't as windy as I thought it was so ultimately it was a waste of time. :(
Having said that I learned a lot, enjoyed the process and may yet use the circuit I installed. :)

Nothing better than running you car off the sun.
I put at least £70 a week in our cars, and don't actually drive that far, but if I could run them off the sun, it would save me over £3500 in liquid motor fuels per year.:eek:
It might be worth considering a Leaf or similar for the daily commute. Their range is pretty poor for going much further but otherwise they are really well put together cars and anyone who has them like them.
 
@Alibro Don't you work with IT? Reason I ask is I was thnking for your domestic off grid energy storage you could upcycle a few computer UPS modules and bigger batteries?
I have several old 3kW APC UPS but they were designed for lead acid so are not optimal for the Li-Ion batteries I have. Also they were designed for standby emergency use so are very inefficient and may not last long if used as a long term solution.
Once I have the solar installed and working I'll look into it. ;)
 
Entertaining latest video Ali.
I think a disc magnet will do what you need, but I'm not 100% sure. I don't think the total diameter will matter though, as long as the magnet can couple cleanly to the rotor.
 
Entertaining latest video Ali.
I think a disc magnet will do what you need, but I'm not 100% sure. I don't think the total diameter will matter though, as long as the magnet can couple cleanly to the rotor.
I bought a ring magnet off ebay hoping it would do the job but it was so weak it's pretty much useless. If the diameter is too small it won't work either so for now I'm moving on. Upgrading the Altymotor can be done anytime.
 
Here is my latest video. Most of it was shot last summer but I only got round to editing and posting today.

 
Work has been quiet recently so I've had time to edit the footage taken over the Summer and Autumn so here's another update. ;)

 
I'm enjoying the new videos Ali. It's all getting very exciting. I can't wait to see it up n running. :D
Thanks mate, unfortunately I'm now pretty much up to date with the videos and I'm bogged down with making the loom for the BMS as I keep changing my mind how to do it.
The master modules are simple as I'd be concerned at the idea of having two BMS modules in the same system. I don't think I have much choice except to remove the circuit boards and connect directly to the cells with ring crimps, leaving a new connector dangling from the module. I'm in the process of doing that now.
The question with the slave modules is do I cut up the eGolf loom and splice into it or remove the blank boards and make new connections?
The reason I'm dithering over it is I want to build the pack and connect the BMS in my office for testing purposes and I don't want to have to remake the entire loom when I go to fit the modules in the car. I'm using these type of connectors https://ebay.us/1GbYXB for the master modules so it makes sense to use them for all the modules.
This means to keep the PCB's I'd need to cut the VW loom leaving a few cm of cable and crimp on the new connectors.
I guess this is the easiest option but I hate the idea of cutting up a loom that might be useful in the future.

I'll edit this post tomorrow and add a few photos to better explain what I'm getting at.

I guess that kinda sums me up tho. I hate destroying (or throwing out) anything that could be useful. :oops:
 
I'll edit this post tomorrow and add a few photos to better explain what I'm getting at.

Yes please. I can't picture what you're saying, so pictures please. ;)

I guess that kinda sums me up tho. I hate destroying (or throwing out) anything that could be useful
I'm the same.

Is it possible to simply make a completely new BMS harness which suits your layout?
 
This is one of the modules with the circuit board removed and my connections added.
The most neg is top left and first pos is bottom left. As this is module number 18 I don't need to connect anything to the negative. The positive of module 17 will be connected to this negative so my BMS connections for M17 will cover that. To connect any BMS you connect the pack negative, then each cell positive in turn so for a 96S pack you need 97 connections.

IMG_20220114_093415411.jpg


This is the circuit diagram for the Nissan Leaf BMS

IMG_20220114_093616609.jpg


And this is the cell count for my modules.

IMG_20220114_093532197.jpg


I decided to keep the module numbers the same as they were in the eGolf pack and add two more. This way if I'm ever able to use the VW BMS it should simplify the change.
This was the layout of the modules in the eGolf pack.
IMG_20220114_093553531.jpg


There is a mistake in the photo above. See if you can spot it.

I'm putting cell numbers on the BMS wires and module numbers on the temperature sensor wires (the bottom two red wires) to help with identification. I'll probably only use a few temperature sensors but decided to bring out connections for all of them anyway.
These are soft PVC cable labels with some clear heatshrink to hold them.
IMG_20220114_093351733 (1).jpg


This is a master module with the PCB still in situ.
IMG_20220114_113412780.jpg


And this is a slave module.
IMG_20220114_113523134.jpg


This is a slave module with a portion of the loom attached.
IMG_20220114_113700610.jpg

For the slave modules I can either remove the PCB and wire them up like the ones above or cut the VW loom a couple of inches from the module and add the same connectors.
If I remove the PCB's then the loom will be kept intact and can be reused in the future if needed but this is much more work and I now have a second loom anyway.
If I keep the PCB's and cut the loom I will have two connectors instead of one so maybe more potential for trouble. But will the OEM connections be better than my ring crimps?
I think I'll just cut the loom. The chances of me needing it again are VERY small.

I want to use the new connectors so that it is easier to build the pack in the office for testing, then move out to the car for installation.
My intention for the battery boxes shown previously is they will have a 28 pin bulkhead connector which these internal connections will go to.
 
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That explains things better Ali.

Do you need to keep the battery master and slave module's for your installation? I figured the Leaf BMS would simply connect directly to the cells in sequence, so it can monitor/balance them, as it would if the cells came from a Nissan?
 
That explains things better Ali.

Do you need to keep the battery master and slave module's for your installation? I figured the Leaf BMS would simply connect directly to the cells in sequence, so it can monitor/balance them, as it would if the cells came from a Nissan?
I am keeping the master module PCB's but they will not be used in this build.
This means all modules are now slaves to the Leaf BMS. ;)
 
I am keeping the master module PCB's but they will not be used in this build.
This means all modules are now slaves to the Leaf BMS. ;)
Cool.

Have you worked out what the battery capacity will be, with the extra modules needed to bring it up to the 96 required by Leaf BMS.
 
Cool.

Have you worked out what the battery capacity will be, with the extra modules needed to bring it up to the 96 required by Leaf BMS.
The original eGolf pack was just over 35kWh so with 88 cells each cell is approx 400wH.
Each module is 4 x 400wH or 1.6kWh.
35+1.6+1.6 = approx 38.2kWh.
I'm hoping I can get around 3 miles to the kWh so hoping for a range just over 100 miles. With careful driving maybe 120 - 140 miles.
 
Just as a matter of interest and apologies for being slightly off topic, have you been watching the Audi RS Q E-tron at the Dakar rally this year? what an amazing piece of kit!
 
Just as a matter of interest and apologies for being slightly off topic, have you been watching the Audi RS Q E-tron at the Dakar rally this year? what an amazing piece of kit!
I haven't seen any Dakar yet but will take a look thanks.
 

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