Live data from Hacker News

Falling lithium-ion battery prices to drive rapid storage uptake

pv-magazine-usa.com

111–120 of 187 posts

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

#111
post #100

Earlier quoted context omitted.

GW is a very important characteristic of an energy storage system, especially as a ratio of GWh. A technology could store 100TWh, but if it can only release 1kW, I'm not interested. The comment you replied to said "just a valid and important measurement as the amount of energy it stores". The comment didn't say power was the same thing as energy, it says that the power is as important as the energy. I don't think thi…

Let me quote that thing for you again. Parse is again, more slowly this time, and see for yourself: > GW is [...] a valid and important measurement as the amount of energy it stores There's no way to sugarcoat it. This is like saying km/h is a measurement of distance.

You're reading it like this:

> GW is [...] a [..] measurement as the amount of energy it stores.

Which doesn't parse. If the text read "of" instead of "as", I might agree with you. As it stands, it doesn't correctly parse either way. Given the full context of the statement, the more likely original intention was that:

> GW is [...] just a[s] valid and important [a] measurement as the amount of energy it stores.

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

#112
post #100

Earlier quoted context omitted.

GW is a very important characteristic of an energy storage system, especially as a ratio of GWh. A technology could store 100TWh, but if it can only release 1kW, I'm not interested. The comment you replied to said "just a valid and important measurement as the amount of energy it stores". The comment didn't say power was the same thing as energy, it says that the power is as important as the energy. I don't think thi…

Let me quote that thing for you again. Parse is again, more slowly this time, and see for yourself: > GW is [...] a valid and important measurement as the amount of energy it stores There's no way to sugarcoat it. This is like saying km/h is a measurement of distance.

Once you fix the obvious typo there, it says "GW is [...] _as_ valid and important measurement as the amount of energy it stores"

Which is entirely true... Both the overall capacity, and the rate at which it can deliver power are critical metrics for an energy storage system.

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

#113
post #56

>IHS Markit expects li-ion battery prices to fall below $200/kWh by 2019 In that article they claim the digit of $200, while you can buy an assembled 1kw/h battery pack in China in retail quantities for around $120 today.

Is that NCA or NMC? Typically grid storage batteries are rated to 10+ years or ~5000 cycles or something on that order of magnitude. One way to get your cells to last that long is to lessen the discharge depth; that may account for some of the price difference.

Most likely consumer grade LiCo with carbon anode. LiFePo modules are twice as expensive, demand for them certainly exceeds supply

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

#114

Earlier quoted context omitted.

>Wrong. At no point do you actually say what was wrong about what you quoted. What do you feel is in error? >GWh is static energy (or simply - energy). GW is energy moving from point A to point B, which is power. Yes, obviously. This is HN. Generally it pays to assume that people know what they are talking about around here. It may be that you don't care about the power rating of the storage instance, but a utility d…

> At no point do you actually say what was wrong about what you quoted. What do you feel is in error? The whole comment past that point is an explanation why that statement is wrong. Read it. You're clearly confused about the difference between power and energy. There's no meaningful discussion on this topic until you figure that out.

Please explain this concept with your understanding of power and energy:

> lithium ion batteries are typically designed with a W:Wh ratio of 1:1 - 1:4

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

#115

Earlier quoted context omitted.

Wow - that's a crazy amount of energy. As a Brit who's never been the south of the US, is that figure really true? 100kWh is about 300 miles in a Tesla, or boiling a kettle constantly for about 30 hours. If that's really accurate, then I'm staggered at how much energy folks must be using to keep cool, and makes my efforts at saving energy seem paltry in comparison.

Remember, the south of the US is in the subtropics, roughly level with the north of Africa. Imagine living in Egypt and not running the AC constantly.

I spent much of last year in Southeast Asia within ten degrees of the equator and rarely had A/C. It wasn't a problem for me, though my computer was often unhappy.

I went to Egypt as a teenager and remember the temperature in Sharm el Sheikh cracking 50C. We would literally sprint from the A/C in the hotel across the beach to the water because the sand was too hot to walk.

Equivalent latitude doesn't mean equivalent climate. As an example, which of these cities is further north, Buffalo, NY, USA or Cannes, France? Hint: it's the one known for topless sunbathing, not the one known for sub-zero outdoor football games.

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

#116

Earlier quoted context omitted.

Or build something like an Earthship ( http://earthship.com/ ). I know that these can air condition a house in New Mexico through geothermal heat transfer, however no idea how they handle the more humid summers of the South East.

They work, but aren't as comfortable as in drier climes. Humidity is tough to control with low-energy, low-maintenance solutions. Unfortunately, many people's discomfort perceptions are heavily influenced by humidity.

I recently moved from Nashville (quite humid) to Flagstaff (quite dry) and the difference is amazing. Large temperature swings are barely noticeable in the dry climate, but would require substantial changes in weight of clothing in the humid one.

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

#117

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…

Germany has plans and investment commitments for a 34 gigawatt-hour plant that will add even more supply to the global battery market.

https://www.bloomberg.com/news/articles/2017-08-03/germany-g...

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

#118

Earlier quoted context omitted.

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.

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?

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

#119
post #96
post #87

Earlier quoted context omitted.

didn't they change it to three shifts to reduce injuries because of human error from being tired

God I hope so. Ford figured this shit out over 100 years ago... 3 shifts maximized factory output. Also having 5 day vs 6 day work weeks didn't significantly reduce factory output, but helped significantly reduce turnover. I swear, it's Musk's biggest weakness, not realizing the costs of mistakes people make when they're tired. I couldn't get through his recent biography because I kept seeing mistake after mistake be…

It is not uncommon for factory workers to prefer 12 hour shifts and working alternating 3 and 4 day work weeks. That staffs a 24x7 operation with four crews of workers.

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

#120
post #85

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…

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.

Post reply on HN