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EV battery output connected to inverter solar input

Hyena

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Jun 28, 2022
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6
Hey guys,
Does anyone know how the MPPT circuitry in an inverter would handle fixed DC voltage instead of the input from solar panels?
I'm wondering if I can connect a 350-400v EV battery to the solar input of an inverter.
The DC voltages are in the same range so technically the 5000w inverter would only pull around 13A from the EV pack to max out it's AC output.

Would this work or is it a recipe for magic smoke ?
 
It's been done here a couple of times, reported on the forum. Maybe it was 200V pack, but same idea.
I would worry about inrush, would like to connect through a light bulb before hard connecting.
 
It's been done here a couple of times, reported on the forum. Maybe it was 200V pack, but same idea.
I would worry about inrush, would like to connect through a light bulb before hard connecting.
Cool, I did a search but couldn't find anything. So much discussion using the same keywords so may have been lost. If anyone who's done it can chime in on how it's going that'd be great.
The inrush is a good point. 2x 240v bulbs in series would probably do the trick!
 
I'm not finding them either.

One guy had an older big-name GT PV inverter and was trying to trick it into operating off-grid with EV battery connected to PV input..
We talked him into getting something like MPP hybrid or similar. It worked batteryless, but wimpy, only started small motors. So I told him to string four car batteries together for 48V. It was able to draw starting surge from that and power larger tools.

Lots of inrush experience around here with lithium batteries and inverters, blows fuses and welds contactors. Don't know if it has blown capacitors or not. Haven't heard of issues feeding PV inputs, but with either lithium or rectified AC I'd want current limit.
 
I remember reading a thread, here or elsewhere, where OP had a prius with 220vdc battery, was able to use a midnite classic 250 (cp? Some special model that was discontinued(?)) with a custom amp/volt curve (like for hydro or wind? Idk) to efficiently move power from his prius to his house power bank. Said gas consumption was on par with a Honda 2000 generator.

Look up "prius solar midnite" I'm sure it'll come up.

Edit: OK I won't be lazy - https://www.solarpaneltalk.com/foru...idnight-classic-as-voltage-converter-possible
 
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Hey guys,
Does anyone know how the MPPT circuitry in an inverter would handle fixed DC voltage instead of the input from solar panels?
I'm wondering if I can connect a 350-400v EV battery to the solar input of an inverter.
The DC voltages are in the same range so technically the 5000w inverter would only pull around 13A from the EV pack to max out it's AC output.

Would this work or is it a recipe for magic smoke ?
Check out https://www.ampernext.com/products/first-30kw-dc-dc-solar-ev-charger/
 
Success: Powering a skillsaw from Prius battery connected to PV input (with automotive starting batteries to supply surge)

 
I remember reading a thread, here or elsewhere, where OP had a prius with 220vdc battery, was able to use a midnite classic 250 (cp? Some special model that was discontinued(?)) with a custom amp/volt curve (like for hydro or wind? Idk) to efficiently move power from his prius to his house power bank. Said gas consumption was on par with a Honda 2000 generator.

Look up "prius solar midnite" I'm sure it'll come up.

Edit: OK I won't be lazy - https://www.solarpaneltalk.com/foru...idnight-classic-as-voltage-converter-possible
I have 2 hybrid cars. Similar in theory to a Prius. Hmm....
 
Remember that guy was using a dead hybrid for power. Considering how fragile the things are I wouldn't tinker with one that ran and or you want to keep running :)
 
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.
 
Does anyone know how the MPPT circuitry in an inverter would handle fixed DC voltage instead of the input from solar panels?
I'm wondering if I can connect a 350-400v EV battery to the solar input of an inverter.
Yes it can. At least with my cheap PowMr inverter.
I did with the 360V battery of my Chevy Bolt (well, a Vanabolt). Details here: https://diysolarforum.com/threads/360v-dc-input-split-phase-120v-240v-ac-inverter.15036/page-4
About inrush current, there is not. Simply connect your inverter and start your EV after. That manner the precharge is done by the EV and there is no inrush to the inverter who simply become another high voltage parts of the EV with the motor controller, DC-DC, charger, heater, AC compressor.
 
Generally speaking an MPPT will not have much 'inrush' anyway because they always start as a high resistance and then work their way down when seeking the max power point, so when initially hooking a power source to an mppt any inrush is constrained by that in the first place. What i would not do is hook a new power source in parallel with an mppt that is already managing a different power source, because there is no guarantee it will not briefly over-current in that scenario.

I have also fed rectified/filtered mains into MPPT as well and had no problems so far. ?
 
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!

Revised for accuracy. The Gen3 eat engines and batteries.

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 have no certifications, but I have personally worked on 500+ Toyota hybrids, and I collaborate with multiple hybrid specialty shops in four locations across the country. The Gen3 are a scourge on the name. Gen4 and newer seem to have sorted the engine issues at least.

The 2023... now that looks pretty luscious... :)

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.

Don't you know it. Honda sticking with the "D" cell package was a horrific mistake that they took to an even greater level with the 06-08 (1 in six failures in 5-7 years) and then again with the 09-11 (1 in three failures in 2-4 years) Civic. I just sold an '05 G1 Insight in December and still have an '02 on the back porch waiting for some love. Yep... both needed batteries.
 
Thanks for the perspective on the gen3s. Unfortunately i never got to work on them (i probably stopped working in shops before they all started breaking out of warranty) and i dont have any contacts in repair industry who deal with them constantly, nor have i personally researched very much into them. So i definitely bow to your greater experience there.
 
Thanks for the perspective on the gen3s. Unfortunately i never got to work on them (i probably stopped working in shops before they all started breaking out of warranty) and i dont have any contacts in repair industry who deal with them constantly, nor have i personally researched very much into them. So i definitely bow to your greater experience there.

You have my sympathies on the Insight. When it comes time to replace the battery, I recommend Matt with HybridRevolt in the Phoenix, AZ area. Mostly a one man show, but he does great work, and he's been at it 10+ years. His communication and customer service is notoriously lacking, thus requiring multiple follow-ups on your part, but the quality of his output is the best in the country.

If you want to pursue your own battery refurb, or a DIY grid charger, I can provide guidance. In the '05 I sold, I had an on-board grid charger installed inside the battery that simply needed an extension cord. :)
 
I am debating how to get it back up and running. I have a whole second pack worth of used cells but at this point ALL of them have been sitting neglected for years straight. I ended up with a 0-300vdc medical power supply i have used as a 'grid charger' in the past, but if i ever do get this project idea rolling i'll probably look into a more permanent solution. Thanks for the offer, I will definitely hit you up if and when i make actual moves. First one will be making it have fuel pressure again so i can start it and move it around, but i'll leave you out of that inanity. :)
 
I am debating how to get it back up and running. I have a whole second pack worth of used cells but at this point ALL of them have been sitting neglected for years straight. I ended up with a 0-300vdc medical power supply i have used as a 'grid charger' in the past, but if i ever do get this project idea rolling i'll probably look into a more permanent solution. Thanks for the offer, I will definitely hit you up if and when i make actual moves. First one will be making it have fuel pressure again so i can start it and move it around, but i'll leave you out of that inanity. :)

I assume you're referring to an electrophoresis power supply. I have like 6 of them. :)

The good news is that the deep discharge experienced by the panasonic cells are actually restorative. It completely obliterates capacity loss due to voltage depression when they're sitting at 0.8V/Cell or less. if they're holding > 1.2V/cell, they're definitely good.

I'll shoot you a PM. There are diagnostic steps you can take right now on the spare pack to weed out bad ones.
 
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!
 
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.
 
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.
 
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.
 
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.
 

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