Battery breakthroughs

Every year or so I get so frustrated with the misuse of units that I have to express myself in a post. I'll go back to keeping quiet now.

 

https://newatlas.com/cheap-alloy-storage-lithium/52031/

http://pubs.acs.org/doi/10.1021/acsenergylett.7b00844

This sounds more realistic than so many lab- originated ideas, in that established manufacturing methods
are used with no exotic alloys or complex processes. COULD this finally be a practical proposition?

https://insideevs.com/tesla-ceo-elon-musk-breakthrough-battery/

 

The Coulombic efficiency is too low at 97.9%, as is the number of cycles at 150. Also, note that while tin is fairly cheap it is also fairly rare, so scaling up may (or may not) cause pricing issues.

At best, there is still a lot of development to go.

 

Had I bothered to read http://pubs.acs.org/doi/10.1021/acsenergylett.7b00844 that data would have been obviuos! Lazy me.
Sites such as New Atlas abound & are fun to read but usually 'cherry pick' the bits that make the best 'news'.
Sadly, another exaggerated claim. What if the Toyota Solid State battery turns out to be exaggerated, too? I'm too optimistic!

 

Have watched all the 'battery breakthrough' reports, good to have all the variants in one place, well done.
Now any & all of these new advances can be entered & we can all express disappointment as they continue
to be not-quite-what-is-being-claimed!

 

Something dramatic WILL happen- whether 'conventional' battery tech or an unexpected new approach. Too many smart people working hard
to make the BIG EV breakout, at a cost/performance point WAY below ICE.

 

relatively old news: https://newatlas.com/nanowire-electrode-hundreds-thousands/42926/

 

This "breakthrough" is now 7 years old, and still my favorite. From http://www.greencarcongress.com/2011/09/alginate-20110909.html

" In a paper published in the journal Science, the team reported mixing silicon nanopowder with alginate to yield a stable battery anode possessing reversible capacity 8 times higher than that of the state of the art graphitic anodes. The anode also demonstrates a coulombic efficiency approaching 100% and has been operated through more than 1,000 charge-discharge cycles without failure."

Seems to hit all the high points with cheap to produce, environmentally friendly process, compatible with common battery manufacturing process. The down side seems to be "The electrodes showed a moderate rate capability, the team found, inferior to that achieved in Si-C composite anodes with hierarchical porosity or in nanowires." Although that seems to be still high at 4200mA/g. No news in 7 years, does anybody know what happened?

 

Then perhaps you'll enjoy this:

 

Yeah, xkcd is a comic I follow. That was a good one.

 

I think the problem with batteries is that there are so many criteria that one has to meet, simultaneously, including

Energy density
Charge power
Discharge power
Robustness regarding high/low temperatures
Efficiency (Energy out / Energy in)
Number of cycles
Safety
Vibration resistance
Toxicity
Cost
Loss of capacity with age
Recyclability
Availability of materials
...
And probably a lot more.

'Breakthroughs' tend to be announced in one area, and as often as not have a bad impact on another area. Sadly they ALL have to be met at the same time.

It is very telling that ICE manufacturers still feel that Lead-acid cells are the best solution for the cars they supply, despite it being over 150 years old technology.

 

Is that not simply they cost far less than L-ion?

 

The rule of thumb for those building EV conversion cars is that if you're going to keep the car long enough to replace the batteries twice -- that is, you're going to have to buy them three times -- then it's cheaper in the long run to buy li-ion batteries.

I don't know why this isn't a factor in gasmobiles. Does the average owner not keep the car long enough to replace the starter battery twice? Maybe most people don't keep their cars as long as I have.

One question we should ask is about performance in sub-zero temperatures. I know that lead-acid battery performance is reduced in very low temperatures, but is it reduced as much as li-ion performance? If lead-acid performs better when it's very cold, that may explain why we have not yet seen any general trend toward using li-ion batteries as starter batteries. Likely another factor is performance when they get hot. I think there's no question that lead-acid batteries are immune to relatively high temperatures, while li-ion batteries clearly are not.

 

I merely meant lead-acid is cheap. It is also very heavy & low-voltage, comparatively. Would a high performance / long range EV be feasible using only lead-acid? 'Relative performance' I'm not familiar with.

 

I just meant "performance" in the general sense, as in how well or poorly any useful thing performs its intended function.

Feasibility of a lead-acid BEV? Well, keep in mind the first generation GM EV1 used a lead-acid battery pack. As soon as the tech was feasible and/or affordable (model year 1999), they changed that for a NiMH battery pack, and got improved range.

In general, only cheap low-speed EVs and conversion vehicles (including some Chinese make EVs) are still using lead-acid batteries. Some PHEVs are still using NiMH battery packs, altho the energy density there is lower, which means they are larger and heavier than li-ion batteries for the same capacity (number of kWh).

So far as I know, all current highway-capable production BEVs use li-ion batteries.
-