i know, i just never thought about coupling a powerwall with essentially the cheap grid-tie inverter. I don’t know why. I guess I forgot they had transfer switches.
Not that it has to do with solar directly but catl announced a new LiFe batttery tech that can charge at 4c, or essentially 10 minutes for 250 miles of range. They are claiming the should achieve mass production by the end of 2023. As far as solar? that probably means the older tech will start to become cheaper.
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That’s great news! Out of all the chemistries I prefer LiFePo4 and Lithium Titanate. Neither require nasty cobalt and neither are as dangerous as Lithium Polymer.
Stay away from Lipo, very high c-rate but short life and easier explode then Li-ion.
Set up a generator. Left or right you cant do without. In a few years there will be a lot of LiFePO4 available from used cars. Perfect for powering a house. Inverters will be available too, just plug your EV batt in. Everything changes fast now. What perfect is now, is old tomorrow. I dont know if I stick to the 48 V Victrons. Works super at the moment, but tomorrow might something else be better. 48v is nice but if power goes up you need a lot of Cu.
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That’s another problem I have. Investing in something now and being left behind the tech support curve and having to start all over again.
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Right. Exactly what I mean. IC with generator stays. That is not going to change in the near furure. PV is fantastic but barely works in winter. CHP is the way to go in my opinion.
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Joep,
Don’t confuse “Lipo” (Lithium Polymer) batteries with Lithium Iron Phosphate batteries (LiFePo4). Lithium Polymer cells love to cause trouble! The latter (LiFePo4) are very stable.
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Lipo is nice for (race)drones not for use in homes, safety and cycles. Very high C-rate.
My 10 kWh pack is LiFePO4 from Littokala with Daly BMS.
Lately I bought some packs for a good price. They are from a E-Golf, still around 35 kWh remaining. Unfortunately they are Li-ion, 12s. The good thing is , this fits direct to the Victrons. 12s is 44V, almost perfect. Downside is the BMS, cant find it 
This is not going to be installed inhouse and bms is gonna be rather expensive. If the packs go in series bms is doable, financial wise…, but voltage is in the range of 350 - 450 V. And then inverter, and then…
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Maybe. It is 10 minutes for 20%-80% charge, so that charge speed was for the middle 400km. It takes 30minutes to go from 20-100%.
They do operate at -10C. But they had no data on density or cycle life. But that is just slightly faster then Tesla’s 15m for 200 miles, but they use a bigger battery pack.
They had CEOs of Chery, Geely, GAC, and Great Wall saying they are going to use their products. Those are large chinese automakers but I don’t think any of them have partnered with a US/Europe automaker.
Geely is the closest because they own Volvo. The rest of them are working on exporting to South America, mexico, and africa and europe.
Not including Tesla seems weird and that was a move prompted by the communist party.
More oddly, the first engineer they brought up and gave a short spiel about they were dedicated to the ideals of a better battery, and he threw in ‘democratizing energy’ and a few other phrases like that, and left the audience I think a bit confused… The CTO comes on, said they were going to work with upstream and downstream providers.
Ford is planning a factory with CATL. But Senate Republicans are investigating the deal over issues of ‘worker rights/slave labor’ for the suppliers.
GM’s next generation ultium chemistry was supposedly almost done a year ago and hinted at similar stats and cited it was cheaper. Which means they may have replaced the last little bit of cobalt. I don’t think it is the same chemistry, it might be but CATL could be trying to be ‘first to market’ with a half-baked product.
GM just inked a deal for a new factory with Samsung, whom Ford has a deal with for their big blue oval manufacturing.
I am just trying to wrap my head around whether or not this is all that significant.
Lithium titanate is great for things like mild hybrids that are small batteries but charge and discharge quickly. However, titanium is mostly sourced from Russia which can lead to some supply issues… Proterra uses them, but they just filed for bankruptcy protection because BYD basically took over the bus market.
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It’s called AC coupling. Yes it works, yes most modern magnum inverters with the arc remote can make it work with but it’s tricky. Basically the inverter tricks the net metered array into “seeing” a grid connection so it starts sending power which the inverter turns around and uses to charge batteries. My understanding is that your micro coupled solar cannot exceed the on board charger’s wattage. It’s a complicated work around which is better avoided by installing a true hybrid inverter. Having said that I find magnum inverters remarkably versatile and tough. My own is 15 years old …
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Agreed. The situation where it seems useful is one where you have a bunch of micro-inverters already in and running. Normally no way to get power without the grid up. With a transfer switch (maybe two), you could charge batteries with the micro-inverters through the Magnum, which would provide the AC 'without the grid. No significant change to the existing system, especially the array wiring.
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Solar pv, here in the Netherlands we have a top arrangement. We can use the grid as a season battery. The surplus in the summer can be used in wintertime. For years I am asking myself for how ling this will last. Well, politics is talking about it. And typical Dutch it is not taken away imediately how Belgium did 
. No, 10% less every year 
. Typical stupid. Imagine how administration looks like. It is a mess already. More proof of the politics have no connection with real life. Another thing is tax. 50% or more is tax on energy and I am not the only one that doesnt have to pay. Everything is shaking in this transition. Now the energy companies banned the pv owners and cant get a long year contract, day deliverance is more expensive, etc etc. Haha, naughty boys or even crooks. Time to cut the cable and go off grid . I always try to just in time but often I am just to late . Hurry up. Sunny days are over. Going to your system JO, hourly prices. More calculations needed.
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Yeah, and this year they are a fraction of last years prices. Not even close to the profit I saw last year.
The good thing is I still delete more than half my own annual “store-bought” consumption, using my own electricity first. What I still have to buy is still rather expensive, since that price consists of mostly taxes.
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Even worse/ bether overhere. Now after two years getting paid a serious amount, energy companies punish you. We will see, the one that adapts is going to survive not the fighter. Anyways, no plans for paying. Bah, hate paying
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Those deals are quickly disappearing in places with heavy solar market penetration because the time of day for peak usage shifted.
California just released like version 3 of it’s policy because they have so much solar during the day which basically pays very little, unless you timeshift it with batteries to one of the peak usage times like evening from like 6-9pm or something like that. then they pay the premium rate. Which is probably you could fudge it to run a gasifier generator during that period then that would pay for your storage.
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So we should report…
We had an eg4 Lifepower go into fault. The software revealed the thermistor had failed. Signature solar asked us to ship the battery back to them and they will send a replacement. It was a big deal, involving palletizing the battery and loading it on the FedEx semitrailer. Everyone at Signature Solar was very helpful and patient. The thermistor failed after 3 cycles.
Our Magnum inverter stopped working about three years in. I originally bought it because it was American and the tech support engineer was English speaking and helpful. They got bought out. The new people won’t answer questions, but if you send them $900 and the inverter, they will tell you what is wrong with it.
I went with Sigineer, a Chinese company with a English speaking Asian engineer named Franklin. He is very helpful. Sigineer has been reliable. We currently are fielding four of these a 3k and three 6k units…all 48v.
I am not so crazy about our CALB lithium iron phosphate 100ah batteries. We have had 8 of them die out of 44. The embarrassing thing is, we got so excited about getting the car running, that we threw all that batteries in at once and never kept track of which vendor the batteries came from…so we have to eat that one. The CALB failures are all the same. Groups of four, go to zero volts. They, then cannot be recharged.
Another important safety tip! Curtis motor controllers cannot take overvoltage, and their failure mode is to provide a dead short to the motor. Geo axle shalves are really tough, we learned that too.
Electric vehicle junkyard
I did find a fun little setup on AliExpress, for configuring used 18650 batteries. I call it the tower of power. It’s a 4s 11p configuration. I also bought a 3s 22p setup too. Both come with BMS, and all the hardware.
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Thanks for reporting, Bruce.
I’m browsing the Sigineer site now. I really like their 3,000 watt split phase inverters. With my electrical setup, I could do cells of inverters and batteries.
I really just need to worry about my well pump and the breaker inside the house.
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I should mention, I am trialing these Leviton double pole double throw (dpdt) switches for transferring power from grid to inverter for a job.
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Hi Bruce , those CALB batteries of yours , do they have the bms and balancer inside the case ? can you open them up , what normally happens is the bms senses a low voltage cut off and then afterwards should re connect once batterys voltage increases slightly if it does not do that auto then maybe you need to open them up and manually try , you mention groups of 4 are they in series ? that’s a no no for battery’s that have the bms inside .
Do you have the AliExpress link to that 18650 tower power ? might be fun to try out .
Dave
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If I am reading their manual for the CA100 manual correctly, they do not, and they require one.
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3) CALB lithium-ion battery products shall be equipped with a special lithium battery management system and lithium battery charger with mode of constant current and voltage limiting. For a few small-capacity batteries are used in series, you can also use lithium batteries protection board of reliable performance;
4) In any case, terminal voltage of single cells must be monitored in real-time. Battery packs in series charging or discharging testing without management system or protective board is forbidden, avoiding battery overcharge or over-discharge.
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The irony is they are $200 each on amazon, and 4 in series to get the 12v, is $800, and Dakota Lithium 12v 100a batteries are 800 or 200a for 1500 from batterymart.com, and Include the bms and such, and i -believe- they can be connected in series, but they also make higher voltage packs as well.
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