2KVA UPS for portable emergency L1 recharging?

[moapys]

Having searched the threads, I’m surprised to see no discussion of this: With the relatively inexpensive hi-power UPSs out there in surplus - has anyone refreshed the batteries and tried it on their Gen-1/~1400W L-1 EVSE? Granted, the A-H won’t get you long/far (unless you double up the cells in parallel) - but still worth a few miles...

Trying to manage range anxiety on tired 2012, in rural-ish Indiana, where the only other “oops” alternative is to travel with beer and trade for 120v time n some farmer’s pole-barn. Again this isn’t other than an emergency carry-along quick-sip approach; it just seems that someone else has worked in IT, has one of these boat anchors, and has given it a try...? Thx for any constructive feedback.

 

[knightmb]

2 kWh could get you +10 miles in hypermile driving, might be enough to reach a faster charging facility, so in a very specific use case, it could be worth the investment.

 

[moapys]

Update - I did implement this (along w/2-pair of marine cells; 2P+2S), and am getting the expected value. The weight is no worse than taking a passenger, and I've validated the charge-to-depletion approach on the UPS, and it works as expected.

Over the holidays, I'll drive the Leaf to a low SoC, and "self-charge" it for several hours, and report back as to how it goes. One variable that remains will be the charge-rate; I've proven that I can drink at 12Amps, but 16Amps might be right on the edge. ...Range-anxiety partially abated!---

 

[bobkart]

 

[ElPresidente]

I have tested using my EcoFlow Delta 2 to charge the Leaf. Works fine, and I can set my EVSE to pull 16 amps and charge a bit faster. The Delta 2 is only 1 KWh, but maybe it’s enough to limp to an L2 charger. The Max version has 2 KWh but I didn’t want to spend that much.

 

[moapys]

Indeed, for the last two posts it comes down to the "tolerance" of the inverter to manage battery voltage-sag. Mine, unfortunately (a free Peak unit bartered last year) only would run for a few minutes before the big lead-acid would drop below is min-voltage threshold: That is largely solved by investing in a (much more costly) LiPo - as shown in the YouTube video - which I was trying to avoid.

Since I did have the UPS, and relatively less expensive banks of lead-acid, the solution was much the same <with the benefit of integral charger for the extender-batteries as part of that UPS>. ...Winter is coming, and I fully expect to have to "take a sip" from the trunk as the temperatures dip!

 

[BrockWI]

I copied this from my other post but I think it applies here as well.

I have the 2013 S that still had a resistive heater (the SL & SV went to heat pumps in 2013). I am not suggesting this, but I had a 8A8D 12v AGM rated at 250A @ 12v or about 2kWh useable. That powered a 2000w pure sine wave inverter. I also connected a 12v charger which kept the 12v above what the Leaf floats at so it wasn't charge by the HV pack. I did try disconnecting it from the HV pack but the car didn't like that (it worked but had error lights) and if anyone else ever used the car and didn't turn on the inverter the 12v could run dead. I typically saw 250-500w being charged to the 12v while driving. I also used a 750w resistance heater connected to the inverter aimed towards my feet and didn't turn on the resistance heat from the HV pack on the car itself. Not that the 750w heater made the cabin as comfortable as the cars HV heat but tolerable for just me on my trip.

Doing all this I typically got about the same range in winter as in summer, in summer my 40 mile round trip was about 60% of my battery and in winter without my charging setup it used 90% of my battery, with the aux battery and inverter I was back to using about 60% of the HV pack or bout 10 more miles.

As my daughter drives this car now and twice a week drive about 100 miles a day away from home with no access to charging, I am tempted to put two of our older 48v 100a lifepo4's or 10kw and a 48v inverter to charge the car with a 120v evse. I tried this and it works but would be messy to install in the car and not sure if my daughter would think it is "cool" to have to plug the Leaf in to itself. On those days she takes our 2012 Volt which get her ~25 miles on electric then starts burning gas. But she doesn't have to worry about range at all.

 

[moapys]

I copied this from my other post but I think it applies here as well.

I have the 2013 S that still had a resistive heater (the SL & SV went to heat pumps in 2013). I am not suggesting this, but I had a 8A8D 12v AGM rated at 250A @ 12v or about 2kWh useable. That powered a 2000w pure sine wave inverter. I also connected a 12v charger which kept the 12v above what the Leaf floats at so it wasn't charge by the HV pack. I did try disconnecting it from the HV pack but the car didn't like that (it worked but had error lights) and if anyone else ever used the car and didn't turn on the inverter the 12v could run dead. I typically saw 250-500w being charged to the 12v while driving. I also used a 750w resistance heater connected to the inverter aimed towards my feet and didn't turn on the resistance heat from the HV pack on the car itself. Not that the 750w heater made the cabin as comfortable as the cars HV heat but tolerable for just me on my trip.

Doing all this I typically got about the same range in winter as in summer, in summer my 40 mile round trip was about 60% of my battery and in winter without my charging setup it used 90% of my battery, with the aux battery and inverter I was back to using about 60% of the HV pack or bout 10 more miles.

As my daughter drives this car now and twice a week drive about 100 miles a day away from home with no access to charging, I am tempted to put two of our older 48v 100a lifepo4's or 10kw and a 48v inverter to charge the car with a 120v evse. I tried this and it works but would be messy to install in the car and not sure if my daughter would think it is "cool" to have to plug the Leaf in to itself. On those days she takes our 2012 Volt which get her ~25 miles on electric then starts burning gas. But she doesn't have to worry about range at all.

Great tips, @BrockWI - thank you for having shared! I'm savvy with most of the above (from a technology standpoint ; e.g. visualizing a "schematic-vs-words"): Do I understand that you added an auxiliary/hefty separate battery <divorced from the Leaf's charing system> and lashed the external electric space heater to that, via the converter? Since I already have lost most of my rear under-shelf hatch area to the UPS/batt-bank, another 'heater' battery could still fit without issue.

We seem to be very much on the same path; I do have a collection of modest home box-heaters of varying power consumption, and had initially planned to repurpose that Peak/2kw inverter to run from the car's 12v with the mindfulness of concern for depletion: I've yet to carefully study the 12v recharging ampacity of the 2012 Leaf, and suspect that - when driving with an inverted space heater - that it might not keep up (e.g. leave the engine 12v discarged with time). I am due for a fresh underhood cell, as mine is over two years old, so expect to cram as large a unit as I can in there, with an eye toward a former radio-station backup battery to try: 'This...after doing the current draw sums to insure that I don't start blowing cigarette lighter fuses, or be forced to pull larger/fused AWG from the engine compartment...

Please feel free to correct assumptions / provide any other gained insights; they are MOST welcomed!!

 

[BrockWI]

If I understand correctly you want to replace the Leaf's 12v with a larger 12v and use that to run run the inverter and possible smaller 120vac heater for the cabin while still charging that from the big traction battery? That won't get you any more range than stock because essentially the traction or high voltage battery will be supplying all the power and running an inverter and 120vac heater which is a resistance heater, which is the same as what's in the Leaf, unless I am missing something? The only way to reduce load on the traction battery, thus giving you more range is to power those loads from some other source that is not charged from the traction battery.

Essentially when I had min that way it was a standalone battery, inverter and cabin heater that I would charge that battery separately at home, using 1 or 2 kWh of heater from another source and not the cars battery.

 

[moapys]

I have tested using my EcoFlow Delta 2 to charge the Leaf. Works fine, and I can set my EVSE to pull 16 amps and charge a bit faster. The Delta 2 is only 1 KWh, but maybe it’s enough to limp to an L2 charger. The Max version has 2 KWh but I didn’t want to spend that much.

My inexpensive 3rd party has adjustable current, and is good for ~12A from the UPS: It happily runs until the four marine batteries are depleted (about an hour): 'Perfect for a sip for the car, if I stop for a couple of beers myself!

 

[moapys]

If I understand correctly you want to replace the Leaf's 12v with a larger 12v and use that to run run the inverter and possible smaller 120vac heater for the cabin while still charging that from the big traction battery? That won't get you any more range than stock because essentially the traction or high voltage battery will be supplying all the power and running an inverter and 120vac heater which is a resistance heater, which is the same as what's in the Leaf, unless I am missing something? The only way to reduce load on the traction battery, thus giving you more range is to power those loads from some other source that is not charged from the traction battery.

Essentially when I had min that way it was a standalone battery, inverter and cabin heater that I would charge that battery separately at home, using 1 or 2 kWh of heater from another source and not the cars battery.

Essentially trying to eliminate "several" autonomous 12v sub-systems; yes. Since the cigaratte lighter is current-constrained (and the Leaf 12v charging algorithm is...unusual), I've gone to another deep-cycle for the space heater, and nightly recharging:

Beyond the modest hassle of clipping on charging leads each evening - and I might go to a quick connect Anderson fitting at some point - it's not a big deal. 'Just another minute of lashing the vehicle to garage cabling, much like a reverse version of Neo plugged into the Matrix pods; just being charged versus providing power!

 

[moapys]

Another update / angle - this involving winter heating "range-loss-abatement"... While not a range-extending approach per se; the net effect of the the following is proving to range-extend a bit:

Rather than use the OEM heating system, I now use the UPS/marine-batteries for my separate space heater <!>: This eliminates the traction-battery draw entirely, and removes that current drain from the range equation entirely. As such, rather than just press-into-service the UPS/EVSE upon traction depletion, I can - in the winter - "go proactive" and use the separate system for as much heat as it want (up to 2kW/x-hrs)...leaving the big battery array for mileage!