The Cost of Everything and the Value of Nothing…

We call them batteries. They are both the bane and enabler of the electric vehicle. A strange paradox in personal mobility for over a century.

The term “battery” derives from Benjamin Franklin’s experiments with capacitors actually – Leyden Jars – that he could use in series to achieve impressive voltages and shocking results. This series of jars
reminded him of “batteries” of canon used in the military.

More properly, the voltaic cell chemically produces a difference in potential between the anode and cathode and when connected to a circuit, will induce a flow of current.

The electric motor dates back to 1837 and by the time of the development of automobiles in the 1880/1890’s, was really fairly mature and much simpler to construct, operate, and maintain than any steam engine, diesel, or gasoline motor. The problem was of course the

A case can be made that Henry Ford actually preferred the electric car and history might have been very very different. In fact, he built several electric prototypes and was such an acolyte of Thomas Edison that he built an identical house next to Edison’s in Fort Myers Florida.
They were close friends virtually their entire lives and Edison had rather promised Ford he would make a battery suitable for an electric vehicle. But this development process stretched to many years before the Edison Nickel Iron cell was perfected and Ford in the interim
had introduced the MOdel T Ford at a price so low it launched what had been a diversion of the very wealthy into a national passion – the automobile.

All for want of a nail. Actually for want of a battery.

The market share for electric cars peeked in the early teens and electric vehicles retreated into the background, lingering for awhile as commercial delivery vehicles, a niche electric car proponents today still point to as a possible area of promise.

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In 1906, an electric car used about 250 Wh per mile and a kWh of electricity was about 20 cents. A gasoline car got about 20 miles per gallon and cost 15-20 cents.

And so to travel 20 miles, a driver faced about 20 cents of expense via gasoline or about $1 in electricity. Basically gasoline was 1/5 the cost of electricity in personal transportation. And it was sold in most stores.

Electricity was almost entirely limited in availability to the downtown area of the larger urban cities.

In 2011 dollars, that 20 cents for a gallon of gasoline is equivalent of $4.97 and we actually pay LESS in real terms for gasoline today than we did 107 years ago. We still get
slightly over 20 miles to the gallon.

Electric cars too still get about 4 miles to the killowatt hour. But electricity has dropped in price by several orders of magnitude, to 11.75 cents per kWh. That would be less than a half penny in 1906 dollars. Further, the U.S. electrical grid has grown to encompass every office, factory, home, garage, chicken coop, and out house in the land.

But the lead acid battery changed very little in that time. Lead acid batteries contain not only lead, but lead oxide as well. Lead oxide is one of the most thoroughly documented and thoroughly effective poisons known to man. It effects every organ in the body but none so much as the nervous system and brain. It mimics necessary minerals such as copper and zinc and so the human body readily absorbs it but to heartbreaking effect. Particularly in children. We think little of it because of familiarity but it is truly one of the most toxic substances in the universe.

It also made every attempt at electric transportation a bit of a nightmare. For two reasons. Pb cells are very very heavy. And Pb cells have a very limited cycle life. Typically 300-350 cycles in cells of the very best construction.

And so efforts at electric vehicle renaisance over the past century has been limited to prototypes and science projects. Yes, you could build a car that would move with an electric motor. But ranges beyond 40 or 50 miles were impractical and the range began decreasing with the first
recharge, becoming ineffective in 2 or 3 years. And the vehicle was always ponderous from the weight.

Late in the century, there were some incremental advances with Nickel Cadmium cells and Nickle Metal Hydride cells. These batteries had marginally better energy to weight ratios but more importantly, longer cycle life expectations. And so interest in electric drive picked up.

To my way of thinking, it was the lithium ion battery that made electric vehicles viable for the first time. Lithium ion batteries rely on an entirely different chemistry to shuttle charges and store energy. They rely on the intercalation of positively charged lithium ions in a negative anode crystalline structure of carbon to store energy. These ions shuttle back and forth between the cathode (when discharging) and the anode (when charging) to effect the storage of electric energy in a chemical format. As such, they represent a bit of a miracle to me.

They have none of the stability problems and memory effects of the Nickel Metal Hydride or Nickel Cadmium cells and none of the toxicity or weight of lead based chemistries. Better, there is little to “wear out” or consume in this repetitive shuttling action and so cycle
life is actually not really very well defined. Certainly 2000-3000 cycles before capacity diminishes to 80% of the original capacity is the norm in the case of Lithium Iron Phosphate cells.

The earliest lithium ionic cells used a Lithium Cobalt Oxide cathode and a carbon anode. These cells still offer the highest energy density but Cobalt is expensive, somewhat rare, a bit toxic, and cobalt oxide releases free oxygen at relatively low temperatures of around 130C. At that temperature it becomes exothermic and will burn to a very hot fire using its own oxygen. LiFePo4 cells, because the phosphorous more tightly binds the oxygen, reaches this point at a much higher temperature beginning around 250C.

But the lithium ionic battery, quite beyond enabling smaller cell phones, laptops with longer operating times, and other small appliances, takes the electric vehicle to a dimension it simply had not enjoyed before – viability..
It could be easily designed into vehicles with ranges of 80 to 100 miles in a world where the national average daily drive is 39.4 miles. The weight of the battery pack to do so – typically 400-600 lbs, was a load the vehicles could carry without particularly
extreme alterations in suspension or geometry and still handled more or less like a car. Perhaps most importantly, the cells would last long enough to make it out of the category of consumable items and into the category of the capital cost of the car. The national average
lifespan from showroom floor to salvage yard of cars in the United States is 9.6 years and the lithium batteries promised an 8 to 10 year life to 80% of capacity.

Dawning awareness of these advantages has caused a near panic – a scramble to see who will profit from the coming age of lithium. This has pervaded not just individuals, or corporations, but indeed governments world wide, with both the Chinese and United States governments
spewing money into supporting companies developing products for which there technically is no yet demonstrable market for their output. This has distorted everything about lithium ion cells to such a degree that NO one can tell what is going on or how it will develop.

In the U.S., both EnerDel and A123, whose bankrupt shell filed this week to have it’s name changed to B456, received HUNDREDS of MILLIONS of dollars from the United States government to develop production lines and jobs for a product they could never demonstrate any economic need for. Indeed, A123 invested $30 million in Fisker Automotive in exchange for Fisker adopting the A123 cells, which had been snubbed by General Motors, so they could claim an OEM customer. In the end, this very act proved the undoing of both companies.

EnerDel performed the same act on THINK, investing over $90 million in THINK in order to be the battery for THink. After both companies received support from the U.S. government, both were sold to a Russian neighbor of the Russian prime minister for less than 10 cents on the dollar.

General Motors of course selected LG Chem as supplier of LIthium Manganese Oxide cells for the Chevy Volt. LG Chem is most noted for building a plant and hiring workers in the U.S. that have never technically made a battery.

Nissan may have topped them all with over a billion in U.S. government support to build their own battery plant in Tennessee, again Lithium Manganese Oxide as the chemistry dujour. But sales of the leaf have dwindled to a few hundred vehicles per month. This month, they allude to the fact
that lowering the price, increasing the range, and introducing their new 2013 model may get them a 1900 unit month.

And so chaos reigns supreme across the battery landscape.

In the Internet, we used to talk about the twelve blind men around the elephant. The analog imagery is of course of 12 blind men arrayed around an elephant. Each feels of the elephant parts nearest to them and then argues with the other 11 about the nature of elephants using what they feel from their perspective as the guide. How the elephant feels is rather subject to where you stand. And so with batteries circa 2013.

The Chinese government wants to play too. But their efforts to encourage electric car use in China have actually not even been as effective as in the U.S. Not to be disuaded, they have sunk billions into building factories to produce cells anyway. And they actively rebate funds to companies who sell them overseas. Curiously, here in the U.S., AFTER paying shipping from China, and customs duties, we can purchase Chinese made cells at less expense than they can in China.

I have examined a reasonably broad array of Lithium cells, and in fact spent quite a bit of time and effort on A123 cells from B456, after they became available from China. But these are again LiFePo4 based cells, as are virtually all of the Chinese prismatic cells. So my part of the elephant looks a lot like LiFePo4 cells, and tends to have instructions in CHinglish.

Among the electric vehicle enthusiasts, instead of “someday – Jerusalem” the cry has been “someday – less expensive cells.” Broadly, I think that can happen. As more electric and hybrid cars are produced and sold, the proven market for batteries will slowly grow as well, perhaps attracting individuals and companies to actually risk in developing better chemistries and production processes.

But for the near term, the market is so distorted by false projections, wishful thinking, and government investment, that I fear all that will be delayed by a great wash out in batteryville.

I regularly hear from viewers just waiting for the price of cells to fall, and a constantly whine from the broader DIY crowd that somehow these cells SHOULD be less expensive, and someone, probably the Chinese is artificially holding the price in the air in some act of gravity defiance designed to deprive us of our cells.

It would not appear so. In fact, my main fear at the moment is that our current supply of ARTIFICIALLY CHEAP cells will dry up at a critical time in the development of the electric vehicle.

I’ve also come to the conclusion that our “cheap Chinese cells” that only DIY and homebrew car builders would settle for, may indeed be QUITE beyond the cells used by Boeing, General Motors, Tesla, et al. MUCH safer. MUCH longer lasting. MUCH more appropriate to vehicle use. And indeed my own bias and crusade against Battery Management Systems may be fueled by the fact that you can get away without it with LiFePo4 cells and perhaps you really DO need one with the more finicky and unstable LiCoO2 chemistry for example.

What if, in an ironic accident of history, WE the great unwashed have better cells at lower prices than anyone else on the planet?

I recently had a conversation with Sinopoly Battery Company Ltd. Our first cells, were purchased from a company in Arizona called Elite Power Systems and they sold a yellow battery they called Thundersky. The head of Thundersky called himself Winston Chung, kind of a westernized Chinese version of the name Chung Hin Kuah. We had good experiences with the Thundersky cells and others did as well and soon Thundersky was the cell for DIY electric vehicles. To expand, Mr. Chung entered into some agreements with some Chinese financiers and the company became publicly traded on the Hong Kong exchange. Within months the financial group and CHung fell out, Chung resigned, sold his stock in the company, and formed a new company Winston Battery Company. Thundersky almost immediately changed THEIR name to Sinopoly Battery Company Ltd and indeed changed the color of the case on their cells, which otherwise appear unchanged. A legal battle ensued that continues to this day. But as of last week I’m informed by Sinopoly and this appears to be confirmed by e-mail from one of the administrative assistants within Winston Battery, WInston CHung has been declared bankrupt in a CHinese court. And while various other aspects of the legal battle will undoubtedly go on for another year or even two, it would appear that Sinopoly has emerged still in the battery business.

Sinopoly is of course publicly traded in HOng Kong, and similarly to the U.S. Securities and Exchange Commission rules, they have to disclose certain information publically as well. Here is their end of 2012 Interim Reportsinopoly2012

A couple of things jump out right away. First the company is expanding production facilities at a bizarre rate. They have expanded their Jilin battery production base and built an entirely new one called the Tianjin battery production base with a by the end of this year goal of producing 250 MILLION ampere hours of battery cells per year.

This is very odd given that their entire sales of cells for the year ending September 30 2012 was some 27,657,000 RMB – about $4.5 million in U.S. dollars and certainly less than 4.5 million ampere hours. Where are these future sales coming from?

And worse, they netted about 2,577,000 RMB or $415,000 USD on the sales – a scant 9.45% profit margin on the sale of cells.

They appear to have 1154 employees or thereabouts and actually lost some $113 million RMB, 10.27 RMB per share. Their largest shareholder and CEO is Mr. Miao Zhenguo.

I would suggest we get the idled LG Chem workers in Michigan to invite the apparently also not very busy workers from Jilin and Tainjin to a series of international bridge and pinochle matches to determine just once and for all who the most capable battery workers in the world really are….

Meanwhile our OEMs are scouring the land actively LOOKING for any source of lithium battery at less than $600 per kWh while I’m sending out a couple of pallets a day at $450 per kWh. Of course they have to have BMS to handle their Lithium Manganese Spinel pouch cells and Panasonic camera batteries, and all we have is things that look like grey bricks and don’t need all that. Our main concern is that the BOLTS not back out.

And os it is in batteryville. Twelve blind men. One elephant. And all the feeling and prodding is making the elephant uncomfortable. She’s afraid the National Highway Transportation Administration will require her to make noises to avoid injuring the blind guys. Both governments spraying shredded currency in all directions. And all our viewers whining furiously that batteries should be cheaper and maybe next year they WILL be cheaper.

It’s a madhouse around here.

For myself, I’m grateful for the peculiarly robust nature of the new CA series of cells we are working with. ANd I desperately hope that the pending changes in shipping regulations, the very meager margins and bottom line losses of teh players, do not threaten the continued supply of these very excellent and by all that I can make out VERY INEXPENSIVE batteries continues. If all this goes up in smoke, we really will be down to making extremely expensive electric cars from extremely expensive and short lived camera batteries bought on eBay.

Everything is relative. Yes, $10,000 is too much for batteries for electric cars. But wishing and whining won’t drop the price at all. The underlying fundamentals would appear to imply that we are stealing battery cells for the moment and the only reason we get away with it is that none of us are doing it in very large amounts for the moment.

The cost of everything. The value of nothing…

Each day, I mount my little Cadillac Escalade and turn the key and drive away. No gasoline. NO fumes. No noise. I never do get over it.

Jack Rickard

44 thoughts on “The Cost of Everything and the Value of Nothing…”

  1. Jarkko Santala


    Good show! On the Thing cooling. How about flipping the fan blade and running it in reverse so that it would suck air from the engine compartment and push it out the vent? This way it wouldn’t heat the inside and natural direction of heat would also be to go up thru the channel.

    I also charged my motorcycle first time since six months. It has been sitting in a cold garage with temperatures down to at least -20 degrees Celsius. First recharge yielded 1.39 Ah into the 40 Ah pack. That would equal about 0.5% monthly self discharge if I had not used the pack at all. However I have spun a couple of motors with it since the last recharge, which explains that 1.39 Ah in full. Hence no self discharge observed.

  2. Great summary of the big picture on batteries. $10k (or even £10k) looks pretty good over 8 years. Until the weekend I was pumping £250 a month on what you guys quaintly refer to as “gas” into my little 1400cc puddle-jumper. That’s £24k over 8 years (OK so the electricity isn’t free but near-as…) Not to mention the brake discs lasting longer because of regen, the free road tax, no oil changes etc.

  3. Predictions for Tuesday. I think Elon himself is going to help fund a rapid growing Supercharger infrastructure. He just announced yesterday that all cars that have been shipped from the factory (supercharger enabled or not) have the Supercharger hardware. If he can get his network built out across the entire country and have all his cars enabled if the owner pays the $2000 access fee. The beauty of this network is that once it is complete, he can approach Nissan, GM and whoever, and he can offer them to have a piece of hardware installed in their car as a $2500 adder that will let them access the Supercharger network. That gives Tesla $2000 profit off of EVERY EV sold that has Supercharger hardware. Seems like a pretty good business. Meanwhile the Supercharger stations with the solar panels will generate surplus power and they also make money on power generation.

  4. In regards to solar chargers on Tesla super chargers: not that great of an idea. Let’s say that a given super charger is used 4 times a day. The charger is 90kW and you’re supposed to be using it for around 30 minutes. That’s 45kWh of energy (not really but it’s hard to know for sure… Let’s say it’s 33kWh just to be more generous). So 33 * 4 = 132kWh of electricity usage per day. A big solar array still tends to be under 10kW per hour. Depending on locale you can expect perhaps 4-7 hours of good light. If we assume the solar cells are a 6kW array and there are 6 hours of good light then the solar cells generate 36kWh of power but cars use 132 so the grid takes up the extra 96kWh. Thus, the charger might be saving a little electricity but nothing compared to what it can use. The upper limit is 48 people per super charger per day. At that rate the solar charging is like using an eyedropper to fill a swimming pool. Even in my initial example, saving 96kWh saves about 0.14 * 96 = $13.44 per day. The solar array is an absolute fortune. Nobody is ever going to make money on that solar array. It is a better idea to just reliably generate electricity at a real power plant (even if it is solar). Power is best generated at large scale.

    If it isn’t obvious, I’m not a huge fan of small time solar installations.

    1. That’s an interesting perspective Colin. It is often true that nice ideas don’t scale when you look at the numbers. However – and I may be (to use the time honoured phrase) typing myself smart here – but it seems to me like it passes a back-of-fag-packet analysis. For comparison the minimum area for a filling station in the UK is apparently 1100 square metres. To keep the numbers simple, assume 1000 square metres of solar panel space is potentially available and each square metre costs £100 and generates 1 kW-hour per day. That is a mega Watt hour a day from an array costing £100k ($150k). That feels like it should be in the zone. Or do you think I’m missing something?

    2. Collin,

      Solar prices are dropping rapidly. The going rate is about $1 per watt. It will take about 40 250W (20KW) solar panels to keep up with one car so the array will cost about $10,000.00. However, given the number of Teslas, charging once per day might be a little bit of a stretch. People will mainly used these only on longer trips. I doubt that these stations will have batteries, they will simply put the power on the grid for credits when they pull power from them for charging. Even if it is not exactly 1:1 the electricity added by the solar cells is clean….

      It is also quite possible that Solar City will work out a deal with surrounding businesses and let them put arrays on their roofs as well…

      Solar has a lot of challenges, but this might be one area where they will work….

    3. If it isn’t obvious, we’re not talking about a small time solar installation. Let’s talk 500 kW producing two megawatt a day. Enough to run a small convenience store with a Starbucks, restroooms, and drop 40 kWh into 50 cars per day. And they’re doing it into a 5 MWh battery pack.

      The problem is, that many rural areas are going to be very difficult to get that much grid power TO. Where Elon’s “mouth is” is in Solar generation of electricity.

      At that scale, they can do 500 kW for a half million. About the same in the cells. About the same in the buildings. With real estate, $2 million per and install 500 across the country. A billion. But funded by ho-hos.

      Lots of J1772 Level II chargers for us commoners.

      This is an automatic bump for SOlar City. You guys buy Tesla stock today. I already did. I’m going to buy Solar City.

      Jack Rickard

  5. I think you should just put second radiator in on the other side, just because you can. And I can’t hurt to be a little extra cool. Especially on a really hot day.

    Can you put some dryer vents (duallies) on the back of that Thing to exhaust the radiators?

  6. John, you might actually be pretty close. I figure 1000 m^2 is probably about 10,000 square feet. A characteristic solar cell I found on ebay would fit about 1300 times in that space. Figuring even the full price you come out to about $226k for the cells. It probably would be $150k or less in volume. This array would also produce about 810kWh per day. If such a structure housed multiple super chargers and each person used 33kWh on average then 24 people could charge without needing to touch the grid. If this happened for 10 years then the total energy saved would be 810kWh * 365.25 * 10 = 2958525kWh. At $0.14 cents nominal cost for that electricity had it been bought from the grid, thats a savings of $414,193.50 so, the system could probably pay for itself in something like 3-4 years. So, I guess it isn’t so crazy so long as you build a big enough array. It actually seems more effective than I thought it’d be.

    1. It’s about scale Collin. Now he could be talkign about changing the rear view mirrors on the MOdel S. I have NO inside information here.

      But when he says its really exciting for Tesla, and he’s going to put his money where his mouth is, his mouth is all the time about Solar energy to drive our cars. I’m thinking a charge station every 100 miles, ENTIRELY run on Solar. 500kW or even 1 MW installations. I’m thinking it is funded by Starbucks and ho-ho sales. And that means he wants MORE traffic than just Model S. Which means AT least Level II for the rest of us and potentially opening up the Tesla supercharger standard and squishing CHaDemo and SAE J1772 Rev B forever. In one smooth move. Licensing the ports to EVERYBODY else including GM and Toyota and Nissan.

      Solar CIty tie. They already buy the stuff. They already install teh stuff. And better yet, they have the financing in place to finance the stuff. Probably the whole buildout WITHOUT any of Elon’s money.

      I like this better the more I work it up.

      Jack Rickard

      1. All four of the Supercharger installations I’ve visited had a 500kva transformer feeding all the switchgear and power distribution. Right now they are only putting in two or three 90kW superchargers feeding two parking stalls each (they share power when both cars are charging…smart sharing where as the full car tapers the other car gets more). With 3 they are barely over half the available power. Seems like room for plenty of expansion. So far all sites look to have identical power equipment, but they have been experimenting with various solar canopies and plug housings.

    1. Now I understand what he meant when he said he wanted to put his money where his mouth is. He’s helping the adoption of EVs, in with this. Although you can opt out any time before three years, depreciation would probably mean you loose money so once you’re in, you’re in for three years. But Elon does make it sound like it’s possible that once you sell your/the car after three years that you could nearly make a little money if it’s worth more than 43 percent plus the cost of the remaining loan, or that it will make a new Tesla better value if Tesla is willing to trade better than 43 percent. I am excited about the other announcements to come.

    2. Now I understand what he meant when he said he wanted to put his money where his mouth is. He’s helping the adoption of EVs with this. Although you can opt out any time before three years, depreciation would probably mean you will loose money if you try to sell before the three years are up, certainly within the first year or two, so once you’re in, you’re in for three years. Elon does make it sound like it’s possible that once you sell your/the car after three years that you could nearly make a little money if it’s worth more than 43 percent plus the cost of the remaining loan, or that it will make a new Tesla better value if Tesla is willing to trade better than 43 percent. So it will help sell Teslas now, and in the future. I am excited about the other announcements to come.

    3. Captain Obvious

      Hurray! Financial aide from the rich to the rich!

      If you can’t afford to buy a car without financing it, you shouldn’t be buying a Tesla.

      How do you calculate estimated net cost/month including gas savings? Does that assume driving the average 38 mile commute each day, or the 1000 miles the car could easily do fast charging? I wouldn’t be surprised if the insurance cost alone was close to the claimed $500/mo.

      1. Captain Obvious

        I doubt every buyer, and every potential buyer can afford to buy the Tesla Model S outright. But I had to laugh at the 500 dollars/month. I would like to see the math behind that.

  7. Here their math and assumptions

    They basically compared it to leasing a Mercedes.

    The biggest lever arms in the calculation is mpg of the car you are comparing too and the business tax benefits.

    and To Captain Obvious… It is obvious that in order for Tesla to become economically viable, the rich DO facilitate adoption. And adding a model S to my insurance is $80/month (too rich for my blood but no where near the 500/mo you claimed)

    1. Captain Obvious

      Looks like Tesla owners claim anywhere from $35-150/mo for insurance. I suppose that depends on how many Teslas the company has had to replace.

      Anyway, with the lease option costing $1100/mo for the cheapest option claiming $500 is Wall Street math. That may fly for congress but not for little people paying bills.

  8. Somewhat off topic; I’m considering purchasing a Nissan Leaf. Now the new Leaf is released in Japan, it seems the remaining Japanese Leafs are all being sold off in the UK at <£18K. Same price as a diesel car.
    Chademo, has always been considered private closed source chargers will be another long term dead end and the original Leaf J1772 charger is only good to 15A, 3.3KW max, a rate of 12 miles an hour to the first Leaf. Many sites around the UK have 16/32A commando plugs which will accommodate the new Leafs bigger charger option nicely.
    From the UK if the weather is reasonable, it is possible to tour a lot of Europe in one of these… Every mile for free!
    Been looking at the world map of installed chademo points. Note how the chademo clustering in the USA varies in interesting ways. It's no Tesla supercharger network by a long mile.
    You still have all disadvantages of owning a fuelled car because it is one. A very nice one at that. It's the price of keeping all options open. 😉
    Buying into Tesla Superchargers? Methinks not a bad move. Offered your garage and expansive roof yet? Noting how the Missouri flows, how about funding an underwater turbine installation like the tidal units they are going to install in Scottish waters? 😉
    If only…

    1. A Leaf at £18k sounds pretty good.

      Not quite all the disadvantages (with the Volt/Ampera); it is a matter of degree. £25 a month on petrol rather than £250, with all that translates into in terms of urban air pollution and violence in the Niger delta.

      And you get a torque band that is a decent shape and a convenient engine speed. Booting it at 3 m.p.h. in pure battery mode when you are giving folk rides provokes an EV grin before you hit 30. Plus my son will ride in it without pulling his hood over his face in case a friend spots him. One of my friends did however opine that it looked like the sort of car driven by a youth with his baseball cap on backwards.

      It is an evolutionary gum tree though. My longest routine day is 130 miles, so an Ampera with the piston engine and all it’s acolytes stripped out and enough batteries for a genuine 160 miles would be the dream ticket.

      Andy we must meet up – I’m in the Midlands. Do drop me a message on Tovey books contact page

    2. Yeah, I’m all excited about the Supercharger network he’s never really ponied up for.

      However the Missouri may flow, we are on the Mississippi, even though we are in Missouri. I know, our rivers and states are a bit confusing.

      Jack Rickard

  9. Jack:
    It’s good that you gave Plug Share a little PR; I have used the map a couple of times to plan a route for a Leaf trip.

    Let me direct your attention to the map and have you look at the gap on I-5 from Sacramento, California to the Oregon state line and tell you both Washington and Oregon have complete their plans to place EVSEs along the I-5 route and have it covered well. The state of California on the other hand should be ashamed because it hasn’t even gotten started on covering I-5 and it is my understand they have the funds to do the work.

    I think it’s time the Governor got the work done. He must be embarrassed to know Washington and Oregon lead California in EV support. .

  10. Jack, the study about cycle-life is really astounding – if I’m assuming the right thing about the term “cycle”:
    As far as I understood, a cycle means taking out (and putting in) the amount of Amp-hours the cell is specified at. E.g. for a 60Ah cell, either taking out 1x 60Ah as well as taking out 10x 6Ah constitutes a cycle. So charging a cell to 100% and discharging it to 11% results in 89% of a cycle. Charging it to 50% and discharging it to 21% is 29% of a cycle. So if the study states, one can do 9000 cycles or more with “Method A”, it means that I could charge the battery 9000 / 0.29 = 31’034 times from 21% to 50% SOC? Or does it mean I can only charge it 9000 times from 21% to 50% SOC? (I hope not because it would mean a difference of “only” about factor 1.5 : e.g. for a 60Ah one could use 2000*0.89*60Ah=106’800Ah until one reaches 80% of capacity against 9000*0.29*60Ah=156’600Ah).
    Could you please (re-)define the term “cycle” in conjunction with this study?

    1. M

      Your definition of cycle is rather rigid, and not supported anywhere that I know of. There are life cycle tests all over the place. And there is no known linear correlation to percentage of discharge or charge, although that is precisely what this test implies.

      A cycle test pretty much defines itself. If you do 500 cycles between 60% SOC and 40% SOC, measure a 2% decrease in capacity, then it is quite acceptable to project 5000 cycles of 60 to 40% SOC.

      To be more precise, and really this is necessary information, you also have to specify the cycle rate. Charge 0.5C and discharge 3C for example. Or charge/discharge 1C.

      So there is nothing to ASSUME about cycle testing. You need the info on WHAT cycle testing we are talking about.

      This study was interesting in that they displayed 2000 cycles of 100% to 11% SOC at 3.76C rate to 80% capacity. But they also showed a variety of OTHER cycle tests on the same graph and in the same tables. One of them was a simulated drive which is becoming more and more common as a metric and indeed there are some “standard” drive cycles you can use. This wasn’t one of them. It was a hybrid bus cycle in Sweden. But it discharged at rates up to 23C and regen charged at rates up to 17C and comprised a 2000 second cycle from 50% down to about 24%. At the end of apparently about 9000 cycles the cells were still at 85% capacity at 35 centigrade and 80% capacity at 23 centigrade.

      As I said in the video, this guy has combined rather a lot of things together in his testing. I like more limited and defined tests. Like doing that driving cycle only at those two temperatures. Or doing it 50% to 25% and 80% to 25%. It lets you isolate and compare things more easily.

      After this test, I’m sure he’s come to the same conclusion. Smaller bite sized pieces of tests are more easy to monitor and duplicate.

      Bottom line, there is no mythical man month here. A cycle is what you define it as.

      The CLOSEST analogy to what we see on the batt specs is Cycle C. Cycle A was actually his reference cycle.

      Jack Rickard

      1. Jack,
        When I look at this test what jumps out to me is the difference between a DC system (blue line-discharge only) and an AC system (braking regen) with brief periods of charging during the braking the bus is doing on it’s route. It looks like an AC drive system is the best way to extend cycle life.

        1. That’s an interesting idea Don, but I’m not sure that these data support it, as we are not comparing like with like. The difference between the red and the blue line is more likely to have been down to the difference in depth of discharge.

        2. Don:

          Perhaps. I do not get that from this data. I would go with SOC levels at this point.

          The effect of alternately charging and discharging is perhaps interesting. But in all that, they were draining the cell, as you do when driving an AC vehicle. The interesting thing about that cycle was they never charged it past 50%.

          Jack Rickard

          1. I guess i was not analysing the graph properly. But there certainly is a lot to be said for keeping the charge voltage lower to get such an increase in cycle life. My plan is to have 34 cells charged with a charger setup for 32 cells.

      2. Jack, thanks for the clarification. Yep, there’s really too much stuffed in there and it gets me confused somehow to be honest. I based my rigid assumption on my background on laptop batteries and a quick check on where they state the following:
        About Battery Cycles
        A charge cycle means using all of the battery’s power, but that doesn’t necessarily mean a single charge. For instance, you could use your notebook for an hour or more one day, using half its power, and then recharge it fully. If you did the same thing the next day, it would count as one charge cycle, not two, so it may take several days to complete a cycle.

        But that’s probably just Apple’s definition of a cycle. Hmm.. so, if going from 50% to 24% SOC and back really constitutes a full cycle, it means that it this procedure in the simulated drive would prolong the life of the battery “only” by about factor 1.5 compared to cycle C. Wouldn’t it be probably better to express battery life not in cycles but in total Amperhours taken/inserted under certain conditions until 80% of capacity is reached? Because in the end the Amperhours and not cycles are what results in driven miles.

  11. Jack,
    You don’t live by the Missouri? D’oh! 😉

    I know more about hang gliding. If only Marcos had a man holding his glider by the front wires. He was caught by what is possibly the most dangerous time to this form of flight. Spring thermals can carry gusts fit to catch your unawares and display them to the World.
    What happened was very nasty, I really hope he gets back to form.
    I paraglide and know full well this time of year can be the undoing of anyone who has been potty trained.
    Drove a Leaf the other day. Oh so NICE! It’s been alluded these are Japanese Leafs being flogged off in the UK. A precursor to the new versions coming out from the UK plant. If Ecotricity fit a Chademo at Keele services, in theory I could make it to John Hardys in a double step and not leave the Highway 😉

    1. Turns out I misunderstood. Marcus was skiiing and maybe over stated the aerobatics. But he is hurt quite badly.

      We live IN Missouri ON the Mississippi.

      Jack Rickard

  12. Jarkko Santala

    Something I realized this morning after chewing on the paper for a while:

    I guess it’s quite obvious to us really, but in the long run undercharging means more range than charging to 100% and this can only take a 1000 cycles or so. So all the reasons they give for Top Balancing (mainly more range) go away immediately. Top Balancing will torture your cells to death in no time at all while the 90% charger is still chugging along with no ill effects whatsoever and with more range left.

    Btw, I found this link to the paper:

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