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Batteries: How cheap can they get?

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151–160 of 311 posts

Re: Batteries: How cheap can they get?

#151
post #4

The cost of 50AH Li-Ion batteries is getting close to the point where they may start to compete with Lead acid for gas powered cars.

Most (not all) EVs still have a 12 volt lead-acid battery: https://www.caranddriver.com/features/a38537243/electric-car....

I understand 12 volts, but why not a 12 volt Li battery? I don't know.

Re: Batteries: How cheap can they get?

#152
post #19

Lifepo4 (lithium iron phosphate) batteries for the home are pretty cheap as of today. Power storage for residential use in a 48v metal rackable linkable system with battery management system (BMS) is $89/kwh shipped/duty paid from reputable chinese suppliers CATL/Seplos etc. You have to wait for sea shipping, add $30/kwh if you want to buy it in the US today. From the same suppliers sodium batteries are currently $13…

Sounds great, but are there actual businesses who will come to your home and do an install, or do you need to to become a mad-scientist electrician and DIY? I got quotes on getting an LG system a few years ago and it was 4X these prices (also for me a problem is that my 'ancient' panels from 2013 use a single inverter instead of microinverters, so if I touch the system I have to replace it all). I keep hoping there w…

If you're in the US, I don't think you need to pull a permit if it's not on your house. So you could build a small installation in your backyard and hook it up without too much trouble.

This channel on youtube is an excellent resource and explains everything for anyone one who is a DIYer.

https://www.youtube.com/@WillProwse

Re: Batteries: How cheap can they get?

#153

Earlier quoted context omitted.

When you say $89/kwh, are you talking about just cells, or assembled packs? I’m just about to buy a 5kw Lifepo4 server rack battery from EG4 for a diy project. It’s closer to $220/kwh This is what I’m planning to buy, but you know something better I’d love to take a look. https://signaturesolar.com/eg4-lifepower4-lithium-battery-48...

Do you know if these batteries be used as a replacement for batteries of a lead-acid UPS? I have a Tripp-Lite rack-mount UPS with an extension battery, but its battery has degraded and it can only sustain my computing load for 3-4 hours. It'd be great to replace it with an LFP battery.

[deleted]

Re: Batteries: How cheap can they get?

#154
I have been predicting over the last year that with many US and European manufacture suddenly giving up on ev growth rate and feed in tariff for solar not getting a good price. The next big thing is going to be home batteries. Looking at what Tesla is charging for powerwall and the actual materials cost which are still dropping people will start trying to get in on these margins.

Re: Batteries: How cheap can they get?

#155
Once material costs fall far enough, other costs start to dominate. Design and permitting, sales and marketing, transport, finance and insurance, installation, support structures, safety systems, interconnections (wires), converters and so on. $11/kWh seems optimistic for 2030.

Re: Batteries: How cheap can they get?

#156

I would love a 5-20kwh battery backup in my home, I even have a place for it. But when I called my local solar/battery installer they said that it was illegal to install grid-charged battery backups in home. I live in Minnesota. They even told me the power from a hypothetical solar rig is sold to the grid utility, not stored, and they give a discount on future winter rates as payment. This seems like a lousy deal.

Perhaps you could circumvent the regulatory inconvenience by getting your "battery" in the form of a Ford F150 Lightning pickup truck. It can power your home during grid outages, and of course can be charged from solar and/or the grid. One vendor is here: https://www.sunrun.com/ev-charging/ford-f150-lightning

Ouch, starting price $57k (98 kwh battery) and around $70k for the recommended model with 131 kwh. It's a rather large vehicle with poor "gas mileage" of about two miles per kwh. A normal sized electric car gets around 2x that, giving higher grid bills or needing bigger solar arrays (thus, more real estate). Idk if the Ford uses LFP batteries these days.

Certainly most of us who think of buying electric vehicles would want to actually drive them around.

Re: Batteries: How cheap can they get?

#157
post #106

I would love a 5-20kwh battery backup in my home, I even have a place for it. But when I called my local solar/battery installer they said that it was illegal to install grid-charged battery backups in home. I live in Minnesota. They even told me the power from a hypothetical solar rig is sold to the grid utility, not stored, and they give a discount on future winter rates as payment. This seems like a lousy deal.

You might as well just buy an electric vehicle with V2L or V2H functionality, and then add a generator outlet to your electric panel. The added benefit is that well, it's a battery strapped to a car. So if you have an extended power outage, you simply drive your car to a charger elsewhere and come back with a full charge. I'm sure Minnesota wouldn't be stupid enough to outlaw EV charging.

There have been weather events and suchlike where it has been impossible to charge an EV, though gas was still available.

Re: Batteries: How cheap can they get?

#158
post #119

Earlier quoted context omitted.

Unlikely that you need more than 10kwh. You just want to cover morning and evening electricity consumption. During the day you recharge and consume directly.

Absolutely agree - I think people fall into a major fallacy with sizing their battery systems. Their power consumption probability* distribution is skewed, and they think their battery needs to be sized for 99% or 100% of their daily consumptions. This gives a drastically oversized battery. Instead, a simple approach is to download the daily power consumption for a year and size the battery for about your 80th-90th p…

Maintaining reliable access to off grid electricity and going net zero are very different applications requiring very different expenditures. Both are valid choices, but going net zero relies on a great deal of grid infrastructure investment and maintenance, and the understanding is that utilities in high home solar areas will rapidly de-emphasize per-kwh pricing in favor of per-month access pricing.

Re: Batteries: How cheap can they get?

#159
post #31

Earlier quoted context omitted.

Yes. Totally disconnected, zero power bill. That home is in a jurisdiction where that is permissible.

How do you get through winter? I’m asking in good faith, I‘m using a PV installation myself and cannot see how I could realistically get off the grid.

Right now?

Using an overprovisioned quantity of cheap cells is part of it.

Insulating and air sealing your home well is part of it.

Thermal mass approaches are part of it. Without cheap batteries, it's very possible to store a great many kwh in volumes of soil, water, or sand riddled with pipes and resistive heaters.

This year it has been pointed out that vertical bifacial solar panels radically outperform tilted arrays if snow is a possibility. Expect this to be the new normal at high latitudes as cell area is very cheap now.

Re: Batteries: How cheap can they get?

#160
this might not be the right thread to ask this question, but I have an older car and the battery inside went. In the past the battery was $50 to replace. Post-COVID, it runs for a whopping $250 at most automotive places... sometimes cheaper on sale.

So why not swap it out for a lithium battery (which still run around $50)? Are there any downsides beyond rewiring the connector types I'm not aware of?

*the battery type is 51R

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