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Trickle charging?

1527 Views 7 Replies 4 Participants Last post by  pictsidhe
Has anyone experimented with low power charging.
Less than 6A or less than ~90V?
That is outside J1772, but the chargers may not object, depending on how anal their designer was.
Also, anyone tried DC through the AC type 1 pins?

I ask as there may be times I want to go off grid. Being able to have the mini sit and eventually charge a bit from 200W solar would be invaluable. If it works, I'd be awful tempted to make a curved solar roof panel.
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As far as I know, you need to supply 360-400VDC to charge the battery, depending on the battery SOC.
So if your solar panel can supply 400VDC, then you can use it. But 200W will be extremely slow.
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Here is the SOC vs Voltage Data I got from my charging session, hope it helps.
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In the uk the Mini comes with a 240v “mains” ( household) charger which has a max output of about 2kw (8A). If it was fed by a 1-2 kw petrol generator it should give about 5-10 miles of range in an hour. I don’t know if the car electrics would accept such a charger, has anyone tried it?
I found the actual J1772 standard. Minimum initial current is 6A. But, it may be possible to lower the current after charging has started. Minimum voltage is probably around 105VAC.
AC level 3 would have allowed lower initial current, but I don't think anyone has implemented it.
I haven't found the protocol for DC charging yet.

If I have to, I can charge a bunch of 18V drill batteries for an hour, then discharge for 30 minutes into the Mini at a power level that will keep it happy. A bit convoluted, though.
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this is the current I see from DC charging,SOC 40% to 99%.

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In the uk the Mini comes with a 240v “mains” ( household) charger which has a max output of about 2kw (8A). If it was fed by a 1-2 kw petrol generator it should give about 5-10 miles of range in an hour. I don’t know if the car electrics would accept such a charger, has anyone tried it?
It will be dependent on the sine wave the generator produces. So short answer is most small generators produce "dirty" power. And dirty power can damage your car. Yes it has been tried, not on a MINI as far as I know. TFL test this theory.
My SE showed up 3 weeks ago. Months sooner than I was told it would!
Initial charging at various power levels suggests the car has an approximate 250W parasitic load in the charging circuit. That is not promising, when I'm looking at around 300W of charging power.

Plan B. There is a big space under the boot floor, that could be used for a small charging pack, perhaps 1kWh. 10x 5Ah 20v tool batteries would work. Solar charges the charging pack, when it is 80%, it then charges the car, along with current solar power. A bit tedious, I probably won't do this.
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