EV battery output connected to inverter solar input

[Vigo]

Interesting!!

I googled that power supply term and didn't come up with anything that looks like what i have. I forget the brand/model but based on the weight and the feel of the centrally located voltage adjustment knob on the front panel, it seems like it has a big transformer in it and is possibly just a rectified variac type thing on the output of a step-up transformer. I do not believe it has any digital components other than for the volts/amps readout. I will try and remember to snap a pic of it. I didn't know what it was when i picked it up for free from a relative's junk pile and got lucky!

 

[Crowz]

Fragile?! I sold my 07 Prius with 279k to my father in law who still has it at just over 400k. I put a timing chain set and maybe crank bearings in it at 300-something thousand. Original battery as far as i know, although obviously degraded it doesn't fault out and the car still works and gets high-30s mpg (down from almost 50 originally). I've done the odd repair here and there but the 2nd gen and newer prii are some of the most reliable vehicles on the planet. I wouldn't call them fragile!

This is coming from an ASE Master Tech who teaches automotive at community college, but still, opinions are opinions, take it for what it's worth.

I wouldn't be surprised if newer stuff would notice the 'missing energy' and need workarounds, but to my knowledge an old Prius won't.

I am still planning to do with with an 01 Honda Insight i have sitting around broken down. That's a 144vdc nominal system. I drove that thing up to 347k. That one i would say is fragile in terms of the original battery design. But that's more of a longevity than a durability thing so fragile still might not be the right word.

Fragile refers to the electrical system not the reliability of any single part of it. Also 279k isn't impressive anymore these days. Most of my older stuff from 2007 and back have over 500k on it.

The electrical parts are not cheap on a prius. This a vehicle that can fall under being totaled (value vs repair cost) if the break booster fails.

$450 to $460 for a USED 2007 abs accumulator. Over a thousands for a new one. Its not like splicing into a chevy or ford pickup to boost your stuff with. Then for the average owner (most are not exactly mechanically savvy I guess from all the tree hugging from the ones Ive met) they get to look forward to the "prius tax". This tax is very similar to the bmw tax or corvette tax. You get charged more because of the myth that goes with they are hard to work on or unreliable in all regards. Both of which are not really true. But they figure you can afford to pay it and don't have a clue that your being milked.

The prius tax is usually worse because its played like the other taxes but they add the hatred for prius owners on top of the normal taxes so labor rates are usually very ugly.

I fixed a friends prius after he had been nailed with the tax in question. They had even deliberately put some of the parts back on wrong in hopes I guess of making it harder when he had them tow it to my place.

Wasn't that hard to work on but the parts prices were beyond ridiculous. So I stick with I wouldn't play with a running one to use as a house battery. Now a dead one? Sure great choice.

 

[sunshine_eggo]

Fragile refers to the electrical system not the reliability of any single part of it. Also 279k isn't impressive anymore these days. Most of my older stuff from 2007 and back have over 500k on it.

The electrical parts are not cheap on a prius. This a vehicle that can fall under being totaled (value vs repair cost) if the break booster fails.

$450 to $460 for a USED 2007 abs accumulator. Over a thousands for a new one. Its not like splicing into a chevy or ford pickup to boost your stuff with. Then for the average owner (most are not exactly mechanically savvy I guess from all the tree hugging from the ones Ive met) they get to look forward to the "prius tax". This tax is very similar to the bmw tax or corvette tax. You get charged more because of the myth that goes with they are hard to work on or unreliable in all regards. Both of which are not really true. But they figure you can afford to pay it and don't have a clue that your being milked.

The prius tax is usually worse because its played like the other taxes but they add the hatred for prius owners on top of the normal taxes so labor rates are usually very ugly.

I fixed a friends prius after he had been nailed with the tax in question. They had even deliberately put some of the parts back on wrong in hopes I guess of making it harder when he had them tow it to my place.

Wasn't that hard to work on but the parts prices were beyond ridiculous. So I stick with I wouldn't play with a running one to use as a house battery. Now a dead one? Sure great choice.

Your experience does not translate to larger markets. There are multiple hybrid specialty shops that do great work at exceptional value. This redneck resentment isn't particularly common in larger markets - particularly where the Prius is so prevalent.

All statements in Gen2 context.

Their inverter coolant pumps are just plain fragile. I'll give you that. In 250K miles, expect to be on the 4th or 5th one at that time (more if you cheap out and go aftermarket). My wife's '08 has 135K on it, and it's on its third genuine Toyota pump. Combo meters and ABS actuators are common enough that there was an extended warranty campaign of 10yr/150K miles, but those are still in the minority by a good measure. Of the 500+ cars I've touched, < 50 have had or needed ABS actuators. combos are more common, but there are DIY drop in options for $150, or DIY capacitor replacement for < $1. I've owned 7 Gen2, and only one had the ABS actuator replaced... when it was 15 years old. 2 of 7 have had bad combo meters. I've probably replace about 50 in 7 years.

ABS actuators mostly fail because almost no one replaces their brake fluid in a Prius. Most don't replace brake pads before 200K miles.

 

[Crowz]

Your experience does not translate to larger markets. There are multiple hybrid specialty shops that do great work at exceptional value. This redneck resentment isn't particularly common in larger markets - particularly where the Prius is so prevalent.

All statements in Gen2 context.

Their inverter coolant pumps are just plain fragile. I'll give you that. In 250K miles, expect to be on the 4th or 5th one at that time (more if you cheap out and go aftermarket). My wife's '08 has 135K on it, and it's on its third genuine Toyota pump. Combo meters and ABS actuators are common enough that there was an extended warranty campaign of 10yr/150K miles, but those are still in the minority by a good measure. Of the 500+ cars I've touched, < 50 have had or needed ABS actuators. combos are more common, but there are DIY drop in options for $150, or DIY capacitor replacement for < $1. I've owned 7 Gen2, and only one had the ABS actuator replaced... when it was 15 years old. 2 of 7 have had bad combo meters. I've probably replace about 50 in 7 years.

ABS actuators mostly fail because almost no one replaces their brake fluid in a Prius. Most don't replace brake pads before 200K miles.

I'm knocking them as being bad cars. I'm saying the average owner should be cautious splicing into one as a mobile battery bank.

If one knows what one is doing that is different than someone running across these threads and diving into splicing into their prius because it looks easy.

Ive worked on several besides the lack of any room to speak of it wasn't that bad repair job wise. I still think hybrids suck vs ev's but that's a personal thing on my part. I can't see hauling a motor around for the joys on a few miles on batteries. I'd rather have a full ev and haul a gas generator around in the trunk if I had to have gas as a backup.

 

[sunshine_eggo]

I'm knocking them as being bad cars.

I disagree. They're among the most reliable cars ever made.

I'm saying the average owner should be cautious splicing into one as a mobile battery bank.

Agree.

If one knows what one is doing that is different than someone running across these threads and diving into splicing into their prius because it looks easy.

Agree

Ive worked on several besides the lack of any room to speak of it wasn't that bad repair job wise.

Have to disagree there. I'm a fat bastid (only 5'10" though), and I have plenty of room. We've transported 10' PVC pipes, 8' 2x4, 65" Philips TV in its box, etc. They have an ass ton more room in them than a Camry.

I still think hybrids suck vs ev's but that's a personal thing on my part. I can't see hauling a motor around for the joys on a few miles on batteries. I'd rather have a full ev and haul a gas generator around in the trunk if I had to have gas as a backup.

Chevy proved this isn't an efficient way to do it. The Volt had a 1.0L generator in the trunk, and once you went on that, you got 30mpg. The next gen got smart and integrated the systems like Toyota/Ford... get your EV miles and then get 50mpg as an efficient hybrid.

No hybrid on the road will give you any meaningful EV range, which is pointless anyway. If you can't plug it in, you're just recharging with gas. Trying to get EV operation in a hybrid is counter productive by every measure. Hello lower mpg and shorter battery life for no gain whatsoever.

Most major changes require a transition. Hybrids are a sensible step towards EV. Plug ins even more so. I personally think that if Chevy hadn't bungled the Volt so badly, they would be more accepted. Everybody jumping to EVs means a LOT of immediate infrastructure improvements that can only happen so fast.

 

[Vigo]

I did the abs module on this one. Its not a terrible job, not much worse than an abs module on a bunch of other cars. My assumption about why they fail is having to do with the extent to which they use the pump motor vs conventional vehicles. An abs hydraulic unit for many cars is $1000 new so thats not out of line either. I think i got a used one for $250 on ebay. I also repaired the combo meter with a capacitor i stole out of an old radio. ?

I just watched a seminar about the Solterra master cylinder which essentially has the abs hydraulic unit and ecm built onto it, as well as the ‘stroke simulator’ for force feedback on the pedal, etc. If those became a common failure point i can imagine the expense..

 

[goingbush]

Hi, New member here. I saw this thread & thought I should add my experience.
I have DIY converted my 4x4 to EV , its my daily driver now for 6 years , it has 45 x 200Ah LiFePo4 prismatic so pushing about 144V @ 500Amp . I recently replaced solar inverter on my house so have a spare Sungrow 5kw Grid Tie inverter .

Just as a thought about how to use excess solar energy , ( I export a lot for very little FIT, only $0.049) I made an experiment & hooked my 144V EV battery up to MPPT solar input . I stood back with PPE incase of smoke / explosion .

The Inverter happily produces 240V but it has some weird algorithm . I'll attach screenshot of production graph over a few hours. The inverter starts with low current & builds up to 12A ( its maximum string input) then falls back to 2A & builds up again over about 2 minuites. It does not get hot.

I tried with another ABB Inverter I bought on marketplace for $100 , it also works, pulls a constant 20 amps & makes about 2.5kwh , but old school inverter has no wifi so no graph.

(For experimental purposes only as its way off code)

 

[yabert]

Just as a thought about how to use excess solar energy, I made an experiment & hooked my 144V EV battery up to MPPT solar input .

Hi. What do you mean about excess solar energy?
When a battery is connect to the MPPT the battery can only discharge to the inverter and not the opposite.

 

[sunshine_eggo]

I suspect it's the MPPT algorithm continuously searching for the sweet spot. Since it's a battery, it's always going to produce peak output at peak current.

It could also be heat related. If the MPPT is hitting max temperature, it may fall back to a lower power, rinse and repeat.

 

[goingbush]

I suspect it's the MPPT algorithm continuously searching for the sweet spot. Since it's a battery, it's always going to produce peak output at peak current.

It could also be heat related. If the MPPT is hitting max temperature, it may fall back to a lower power, rinse and repeat.

Yes correct. The battery is capable of 500Amp , The Max MPPT inverter input is 12.5Amp , so it can't pull any more than that. But its definetly not heat related . If I watch the BMS Display in the car when I hook the battery to the Solar input the weird algorithm shows from the beginning. Even after a few hours running the Inverter is no warmer than it would get on a sunny day .

When the inverter was on the house PV system it would clip at 12.5Amps and show a similar output . ( I replaced the original panels with newer 15Amp panels)

 

[goingbush]

Hi. What do you mean about excess solar energy?
When a battery is connect to the MPPT the battery can only discharge to the inverter and not the opposite.

During the day I export more solar to the grid than I can use (in summer) even after charging the car, and only earn $0.049 FIT . , that is excess .
I won't comment on you thinking I might expect to charge a battery via MPPT input.

At the end of the day I have a fully charged car battery via its 3.3kwh onboard charger which I plug into a 20A outlet, my idea was to use some of that in the evening rather than pay for power from the grid at $0.26kwh.

OK Ideally I get a Hybrid inverter and buy batteries for $6000 for a questionable ROI ,
but I have 28kwh of battery sitting right there in my car.

 

[yabert]

... that is excess .
I won't comment on you thinking I might expect to charge a battery via MPPT input.

Haha! sorry if this has offended you.
English is not my first language and I didn't know how to ask detail with few words write in a discussion forum.

There is many peoples here who have or are interest to have their EV part of the solar/battery system and there is few challenge with current technology.
Myself, I connect my EV conversion with his 64 kWh battery to charge the house battery sometime.
It work, but it's far from plug and play
So, thanks to share you experiment.
Do you share details about you conversion somewhere? EV conversions are always interesting to see.

 

[goingbush]

Haha! sorry if this has offended you.
English is not my first language and I didn't know how to ask detail with few words write in a discussion forum.

There is many peoples here who have or are interest to have their EV part of the solar/battery system and there is few challenge with current technology.
Myself, I connect my EV conversion with his 64 kWh battery to charge the house battery sometime.
It work, but it's far from plug and play
So, thanks to share you experiment.
Do you share details about you conversion somewhere? EV conversions are always interesting to see.

Vigo, no problems, I struggle with English too and it is my first language
I converted my 1973 LandRover , Old school conversion before it was easy to buy salvage EV parts . i enjoy it so much its my daily driver . Here is my build
http://goingbush.com/ptev.html . I really need to update as its a long time ago now . The prismatic cells are still performing well.

 

[Vigo]

That's an excellent conversion writeup, thanks for sharing! Very cool vehicle!!

 

[goingbush]

I just recieve PowMr inverter today $300 , I intend to use it to run my 240V fish pond pump from solar & a backup battery but first I tried to make magic smoke by connecting MPPT to my EV battery. This is so cool, Im going to mount one in a pelican case with some safe connectors to use as a Power source to keep fridge running when the grid goes down (it happens a lot here) . At the moment i only have GTI inverters.

 

[yabert]

I just recieve PowMr inverter today $300 ... This is so cool

Yes, it's clearly unbelievable to have such features for 200-300$.
My PowMr 2400W still run a part of the house since near 2 years now. Solar panel always hook to the MPPT and 2-3 time a year I connect my Vanabolt (360Vdc) to the MPPT in order to charge the home battery when grid is down.

 

[sunshine_eggo]

I got the PowMr 24/3000 120VAC as an early x-mas present... still gnawing on bunch of used cells to get the LFP battery up and running. Looking forward to finally seeing what it can do.

 

[AussieDave]

Apologies for reviving an older thread but this is the closest thing I've seen to something I've been brainstorming.
I currently have a 5kW solar array feeding two strings connected to a 6kW Grid Tied Inverter.
Also have an AC Coupled 5kW Alpha ESS.

I'm about to purchase an EV with V2L capability. Unfortunately being V2L rather than V2G means it can't sync 50Hz AC with the grid. Hence my idea.

Attach the 220v AC output from the vehicle to a high output AC-DC rectifier which puts out 220vDC @ 3 amps (already seen a version I think will work)

Attach this to an input string of my grid tied inverter via a DC-DC Auto Changeover Switch.
So when that string reaches 0VDC (as the sun goes down), the Changeover switch swaps the input to the now DC output from the vehicle.
This DC from the vehicle is then used seamlessly with the grid as the inverter should treat it as if the Solar panels are producing power and therefore feed the entire house. If the output from the vehicle isn't enough, the grid tied inverter should then supplement from the grid.

Thoughts????

 

[Vigo]

Rectifying 220vac will give you something more like 350vdc so your components have to be designed around that.

I dont know anything about an auto changeover switch but i do know that the timing of dark hours is highly predictable so you could simply run it off a programmable timer switch.

You would need to be able to set your MPPT to only draw as much as the vehicle's onboard inverter can support. That's IF your mppt is 'larger' than the vehicle inverter.

 

[AussieDave]

Rectifying 220vac will give you something more like 350vdc so your components have to be designed around that.

Yeah a direct rectified current would provide 350VDC, I was thinking of using this VARIABLE unit to provide 220-240VDC at 3A to match the Voltage and current from that PV string input.
Wouldn't need to change the existing grid tied inverter this way.

https://www.aliexpress.com/item/1005003714947164.html