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Falling lithium-ion battery prices to drive rapid storage uptake

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Re: Falling lithium-ion battery prices to drive rapid storage uptake

#121

Post by hwillis »

leggomylibro wrote: post #55
comicjk wrote: post #38

Using lithium-ion batteries for stationary storage is interesting because their original advantage was all about light weight (lithium is the lightest metal element). Now, it seems the development effort devoted to lithium-ion has paid off so well that they are the best OVERALL battery solution. The single-minded effort we put into cell phones and cars is so strong that it now reaches all the way to homes and the gri…

Don't lithium-ion batteries degrade extremely quickly, though? Won't these all be down to half capacity or so within a decade? Is it really worth investing in gargantuan quantities of energy storage if they need to be replaced every few years? I'd be eyeing EDLC technologies or something like molten salts over giant stationary phone/laptop/car/etc batteries.

Li-ion batteries have the second slowest self-discharge of any battery and the longest cycle life/easiest upkeep.

An li-ion battery will do about 500 discharge cycles from 0-100. They'll do several thousand from 20-80, and tens of thousands cycles from 30-70%. If you have a few days of storage, the battery as a whole will last an incredibly long time even when cycled every day.

As for why: When the battery is kept at a high or low voltage, it puts an overpotential on one side or the other of the battery. There's more or less lithium on one side of the battery and it tries to diffuse across the battery very slowly. It never makes it to the other side and reacts with the electrolyte and is lost, reducing capacity.

The closer it is to 50%, the less lithium is pulled/pushed out into the electrolyte.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#122

Post by hwillis »

HillaryBriss wrote: post #118
wongarsu wrote: post #74

Earlier quoted context omitted.

They degrade extremely quickly in the usage pattern of a typical consumer device (alternating between full charge and full discharge). They last fairly long if you keep them between 30% and 80% charge. It's not the most long-lasting technology, but we replace most infrastructure every 20-years already. A 10 year lifetime wouldn't be that bad.

> They last fairly long if you keep them between 30% and 80% charge wait. does that mean that, effectively, for a careful Tesla owner seeking to maximize battery life, most of the time her practical range will be roughly 70% of the stated value?

Teslas have a "trip" mode. During normal operation they charge to 80%, but if you put it in trip mode it charges to 100%.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#123

Post by hwillis »

fenwick67 wrote: post #4

> By 2025, the world’s base of cumulative installed storage capacity will reach 52 GW, IHS Markit says, up from around 4 GW today. Last year, 1.3 GW of grid-connected storage was deployed globally, and this rate is poised to accelerate to 4.7 GW a year by 2020, and 8.8 GW annually by 2025. GW is not a unity of energy storage capacity. It's a unit of power.

It's weird and not usually reported like that. Possibly it is a typo, but either way it's relatively closely coupled to storage capacity: li-ion is typically used around 1C, so ~1.3 GWh of capacity was deployed, within a factor of two or so.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#124

Post by hwillis »

nabla9 wrote: post #66
Someone wrote: post #6

Earlier quoted context omitted.

Why wouldn't recycling be an option? Chances are that, if large batteries become commonplace, it will be cheaper to mine lithium from used batteries than to do so from the earth because they will have very high lithium content. Also, covering 1/3 of daily use seems low to me. It wouldn't get one through a few windless winter days with dense cloud cover, for example.

Extraction of lithium from old batteries is five times more expensive as mining lithium. At some point it may become profitable. On the other hand, there is lots of lithium. If the environmental impact of lithium mining going off the roof is not a problem, there is no reason to reuse.

>Extraction of lithium from old batteries is five times more expensive as mining lithium.

Even as an upper bound that's still a silly thing to say. It means comparing a lab-scale extraction with massive multinational, highly-automated mining operations. At scale lithium recycling would certainly be much cheaper than five times more expensive.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#125

Post by petra »

hwillis wrote: post #120
briffle wrote: post #85

Earlier quoted context omitted.

Pretty sure they will also use the batteries in their powerwall's as well (I seem to remember that the grid storage in CA was produced with batteries from the gigafactory) I would imagine they would quickly switch the powerwall to use the new battery size that the gigafactory is producing..

The powerwalls and powerpacks use a different chemistry from the cars, and are still using the 18650 size going forward. It's trivially easy to change the size of cylindrical batteries. Li-ion batteries are essentially a tape, and the second to last step of production is to roll the tape up and insert it into the battery. Different cells just require different cans and widths of tape.

What about a different chemistry , like Li-Sulfur ? how big of a change the gigafactory will require ?

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#126

Post by thescriptkiddie »

ChuckMcM wrote: post #35

I wonder how much of this is simply the Gigafactory coming online at full production + others trying to keep their factories running. If you look at Tesla's plan to be making 10,000 model 3's a week, with a nominal 90 kWh battery in each that is 900 MWh a week of capacity or 46 GWh capacity a year. But it is all tied up in cars of course[1]. The power companies have been screwing around with rate plans to keep grid-t…

Utilities are actually planning on using parked electric cars for storage.

https://en.wikipedia.org/wiki/Vehicle-to-grid

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#127

Post by hwillis »

nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

>It's workable and scales if we are able to reuse lithium. When does that happen? (recycling is not reuse)

I assume you mean reuse is not recycling ie using old batteries as lower-capacity storage is not workable indefinitely.

First off the most pressing issue is that there is no practical replacement for cobalt in many li-ion applications. Chemistries without cobalt, like lithium titanate or iron phosphate, have a price and weight premium and reduced capacity. Cobalt is rarer than lithium, makes up more of the battery, and is harder to mine. The price might go up very quickly past a certain point, if supply from the DRC becomes tighter.

Lithium is very widespread and relatively abundant but most importantly its final impact on the price of a battery is only a few percent. If it becomes more expensive to reclaim or mine, it will still have a pretty small impact on the cost of batteries.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#128

Post by mebreuer »

fenwick67 wrote: post #106
epistasis wrote: post #25

Earlier quoted context omitted.

Your instincts would be wrong on this one. This is a technical article, that talks about all the right things for grid storage: value stacking, $/kWh (note the h), various install locations such as behind-the-meter, etc. They know what they are talking about. Currently, grid discussions happen mostly in the MW or GW space. Maximum instantaneous discharge speed is pretty much the most important characteristic for stor…

I think what threw me off was when they say "capacity". I don't work in power systems, I work with low-voltage DC stuff, so when I think "the capacity of the battery system" I think it would mean the maximum stored energy. But "The maximum amount that can be produced" is also a valid definition of capacity, and I'm guessing this definition might be used in power generation more often ("the generator is operating at h…

Exactly.

If you're interested, the context is that capacity was historically used in the utilities industry to refer to generation capacity, which is in MW or GW. E.g., the capacity of a power plant could be 500 MW, which for the decades of power production preceding renewables, could be sustained indefinitely as long as you're feeding it fuel.

By extension, when you talk about battery capacity in the context of the electrical grid, you're talking about the MW or GW of generation that you can replace during peak loads. The ability to distribute batteries across a grid to meet peak demand (and defer infrastructure/peaker plant construction) is the best way (today) to justify investments in batteries.

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#129

Post by sp332 »

hwillis wrote: post #120
briffle wrote: post #85

Earlier quoted context omitted.

Pretty sure they will also use the batteries in their powerwall's as well (I seem to remember that the grid storage in CA was produced with batteries from the gigafactory) I would imagine they would quickly switch the powerwall to use the new battery size that the gigafactory is producing..

The powerwalls and powerpacks use a different chemistry from the cars, and are still using the 18650 size going forward. It's trivially easy to change the size of cylindrical batteries. Li-ion batteries are essentially a tape, and the second to last step of production is to roll the tape up and insert it into the battery. Different cells just require different cans and widths of tape.

I'm pretty sure Powerwall 2 uses the same 2170 cells as the Model 3. https://en.wikipedia.org/wiki/Tesla_Powerwall#Technology and see the note on 2170 cells on this page https://en.wikipedia.org/wiki/List_of_battery_sizes#Lithium-...

Re: Falling lithium-ion battery prices to drive rapid storage uptake

#130

Post by markvdb »

Beltiras wrote: post #19
nabla9 wrote: post #2

$200/kWh by 2019. Assuming that households consume between 30 kWh and 15 kWh electricity daily on average and you want to have storage capacity for 1/3 of daily electricity consumption to get wind or solar energy work, you need 10-5 kWh per household. That's $2000 - $1000 per household. If that battery lasts 10 years, its $200 - $100 per year. It's workable and scales if we are able to reuse lithium. When does that h…

There is another way of thinking about the economics of this. IIRC the typical price is 12 cents per kwhr. You would need to utilize the battery in sold energy no less than 2000 cycles just to break even. About 5 1/2 years of constant monetized operation (which is a ludicrous proposal). And this assumes no cost on the energy production side.

Electricity price is more like .26€ here(~.31$), and this is certainly not the most expensive place in the EU. Mostly network charges and taxes.

Going off the electric grid should become fairly easy. Cheap solar and storage should make this feasible for an eco-conscious household...

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