How to view the modem status pins on a serial port in Ubuntu linux.

12 November 2014 · Topic: Music · Tags:

Whoa there!!!

I know… I know what you might be thinking. What is a post like this doing in an engineering blog. Engineers are often musicians and writers. Not necessarily great ones mind you, but sometimes when you watch your family during the holidays, words just pop into your head.

Here is a retread of the 400+ year old hymn (We Wish You a Merry Christmas) out for Christmas 2014.

We Wish You a White Trash Christmas

We wish you a white trash Christmas,
We wish you a white trash Christmas,
We wish you a white trash Christmas,
And a tasty cold beer.

Chorus
Good tidings we bring to you and your kin,
We wish you a white-trash Christmas
And a tasty cold beer.

Grandma buys us gifts from offshore,
Grandma buys us gifts from offshore,
Grandma buys us gifts from offshore,
They don’t last one year.

[Chorus]

Grandpa pees with the door open,
Grandpa pees with the door open,
Grandpa pees with the door open,
So we can all hear.

[Chorus]

My cousins bring the main entree,
My cousins bring the main entree,
My cousins bring the main entree,
Its the rump of a deer.

[Chorus]

The in-laws are always fighting,
The in-laws are always fighting,
The in-laws are always fighting,
The kids hide in fear.

[Chorus]

My sis gives the gift of ammo,
My sis gives the gift of ammo,
My sis gives the gift of ammo,
We all can now cheer.

[Chorus]

We wish you a white trash Christmas,
We wish you a white trash Christmas,
We wish you a white trash Christmas,
And a tasty cold beer.

Merry Christmas

Copyright John S. Huggins

You think I’m making the lyrics up?

HahahaHAaah LOL LOL LOL lol… sigh… no 🙁

What follows is a letter of praise sent to the staff at LR Baggs.

===========================

After producing a Christmas music/drama variety show at our Church last Sunday I feel compelled to share my experiences with LR Baggs vs. other solutions that arrived during sound check. As many of you likely understand, sound check for a slew of different music groups is a nightmare at worst and challenging at best. Without going into too many details, sound check is a time for the house system to wring out its gear and mentally prepare for the segue between groups. This is not the time to debug the internal electronics for the performers’ acoustic guitars. Right?

Wrong.

Of the four initial acoustic guitars with installed pickup systems, only two, using Drum & Strum installed LR Baggs units, worked flawlessly. Other plain acoustics using sound-hole pickup systems also worked well. I can’t say the same about two other “high end” guitars with built-in electronics that caused no end of trouble during our sound check. The first guitar clipped and then… fed back and then… became unusable. A second of the same brand was swapped in – didn’t work. The quick thinking owners of these issue prone guitars borrowed our Norman and a “save the day” PRS acoustic (PRS Acoustic? Who knew?) that wandered in the door in response to a plea for functioning guitars. I’m not going to mention the brand of the otherwise superb guitars with coffee can sounding electronics other than to say some trade names rhyme with “depression.” My guess is the guitars’ batteries were low and these things seem to eat batteries like candy. I’m surprised the guitars from this maker don’t come with a replacement battery bandolier to wear on stage. Or, perhaps, they should just swallow their pride and create an external power supply solution. Alembic does this very well so this is not an odd concept.

Now I come to the point of this message. The above Norman guitar and my Fender (yes Fender) 12 string acoustic both had LR Baggs pickups installed last year: Anthem SL and Anthem respectively. Since these two guitars were never scheduled to play at the same time, they shared one LR Baggs Venue DI with easy, pop-free, swapping via the mute/tune switch on the Venue. This show vindicated my decision to choose LR Baggs for my pickup and DI needs.

Let me preface my final point by stating I am an electrical engineer by trade with over two decades of circuit design experience including plenty of analog work. When I was first turned on to LR Baggs I reviewed their, and other, products with a critical eye towards value, not price. Once I discovered the Anthem Mic/UST hybrid with crossover mixing approach I thought to myself “Hey, that’s good thinking.”  Believe me, I was hesitant to put a $299 Anthem system into a $250 Fender 12 string, but this particular guitar has earned its stripes and I was tired of micing it. I purchased the Anthems for installation by the local luthier at Drum and Strum. Other than a bit of gain difference between the two guitars, the Anthem SL-Norman combo has more signal, the whole LR Baggs approach has earned the highest accolade I can give an analog audio system… and that sums to one simple word…

Transparency

With my examples of LR Baggs product installations, you don’t notice the system is there. It just works well. It is transparent. My cheap guitar benefits greatly and others notice. Can you tell a difference between the Anthem vs. natural sound? Of course you can, but you have to focus to notice. Whereas the high end guitars mentioned above have pickup systems that are unmistakably “electric”  sounding when and if they work; The owners of these guitars deserve better.

There is a saying “You only buy quality once.”  So far this is ringing true for my handpicked LR Baggs solution for my not-so-high-end guitars. You did not let me down. The sting felt to the wallet when I purchased your products has long since faded away in the Joyful Noise of beautiful acoustic sounds celebrating Christmas.

So thank you LR Baggs for making my electrified acoustics not part of the problem during sound check and the performance.

Merry Christmas.

John

Thanks to the efforts of a great many antenna enthusiasts, the Hoverman design is reborn to help TV viewers obtain off the air (OTA) television signals.

On my hamradio site I document some history, manufacture and testing of a modern version of the venerable Doyt Hoverman UHF TV antenna.

Please enjoy Superbowl TV Antenna.

The circuit below is a straight forward way to provide continuous control over the intensity of one or more LEDs using a current regulator circuit based on a crude current mirror.

Linear LED Intensity Controller

Linear Regulator LED Intensity Controller

Summary

  • Q1 buffers the potentiometer voltage a little.
  • Size R2 for maximum current through the LEDs.
  • Q3 “mirrors” the current pushed through Q2 despite the voltage drop of the LED string.
  • The compliance range of Q3 is the battery voltage less about 1V.
  • R3 and R4 are optional, but improve the balance of the mirror by reducing the variability of emitter resistance.
  • DS2 is optional, but you should be able to fit as many LEDs as the voltage range allows between 9V and the collector of Q3.
  • The lowest 20% or so of potentiometer swing results in insufficient voltage to overcome the two Vbe drops of Q1 and Q2 leaving the upper 80% to control brightness.

Details

Circuit Description
This circuit is simply a voltage to current converter with almost all battery voltage available on the output.

There isn’t a way to reliably control an LED with voltage as it is very much a current device. The attached circuit will take a voltage, set with the pot, buffer it a bit with Q1 and apply that voltage to R2. R2 changes voltage to a current which flows through the left side of the current mirror Q2 and Q3. Q3 will do whatever it takes to draw the same current through the series LEDs. Q3 essentially becomes a linear current regulator, controlled by the voltage made by pot R1, which is exactly what you want to regulate LED brightness.

The current mirror ratio is close to 1:1, but variances in transistors will cause some imbalance. The addition of R3 and R4 help to immunize the current ratio from transistor tolerances and alleviate the need for a matched pair of transistors.

There are simpler ways to create a controllable current regulator, but not by much. This is pretty robust.

R2 Controls Max Current
Note that the max current is governed by R2 which is sized just like you would for an LED in series with a battery. One small difference is Q1 and Q2 both have ~0.7 volt drop so the voltage across R2 is about 9-(2*0.7) or a little over 7V.

Potentiometer Partial Use
The LED is off for the first 20% or so of its setting due to the Vbe of Q1 and Q2. The remaining 80% smoothly controls current through the LED. If this bothers you, place one forward bias diode in series between the bottom of the pot and its ground connection. This will raise the minimum voltage 0.7 V or so and reduce the dead zone a bit. It’s up to you if adding one more component is worth expanding the potentiometer range a tiny bit.

Voltage to Current Converter
This circuit simply converts a voltage appearing on top of R2 to current through the LED, while keeping full voltage available for the LED string. In this example, R1 and Q1 provide the voltage, but any voltage will do.

Before you start on your next electrical schematic diagram you need to understand what a drawing is, how it is organized and who governs the format of drawings.

Many times schematics are thought to be exempt from this formality, but nothing could be farther from the truth.
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The desire to be green exists in most of us I am sure. However, not all of us have cash on hand to “contribute” to the solar industry. What follows is the analysis of one family’s planning to use free solar energy without breaking the bank.

Preface:

My wife thinks I am a greeny weeny in my quest to harness the free energy from that big star out there. I say I am just trying to use Star Power. I like that name better than Solar Energy.

Being green is certainly a goal all of us should adopt. Available green energy options cost from cheap to ridiculous. Difficulty ranges from easy to difficult. A conservative at heart, my green options have to stand the test of at least basic financial scrutiny. An electrical engineer by trade, I am a brutal reviewer of the soundness of the various systems.

The Internet documents a large amount of do it yourself (DIY) projects. The home-brew approach is nothing new in the alternative energy crowd. I have a book from the early seventies that discusses most of the same things we see documented today. The Internet is a great library of these efforts. Your initial research will be rewarded with more data than you can digest in one sitting. Don’t fret. It takes a while and you need to watch out for some very incorrect information from folks who just don’t know what they are doing. The good news is many folks have done a fine job of documenting their experiments with real data available for your review. Very nice.

My stated goal is to harness “Star Power” to offset at least some of my energy consumption and do so with economic common sense.

Highlights include:

  • Philanthropists Welcome
  • Incentives
  • Return on Investment
  • Energy Payback
  • Evaluation Criteria
  • PV Solar Electric
  • Wind Electric
  • Thermal Solar Hot Water

Philanthropists Welcome

What we are about to reveal below is just how un-economic many of the alternative energy approaches are. Many folks still pour cash into systems that cannot ever hope to be cash positive in any reasonable amount of time. They know this and still choose to do it because of their honest desire to be “good” to the Earth. I applaud anyone who contributes their hard earned cash towards the reduction in energy consumption from fossil fuels, etc. without expectation of financial reward. This is what I will call “Environmental Philanthropy.” Bravo to all of you who do this and accept my sincere thanks for what you are doing for your fellow man.

Incentives

Unless you pay no attention to just about everything, you know there are exceptional financial incentives available in the form of tax credits and other benefits from Federal all the way down to local governments. These are OK, but there is a potential flaw in partaking of these benefits. You are spreading your costs to your fellow citizens in exchange for helping reduce energy consumption. Our elected representatives think this is an OK thing to do so we are stuck with it. In the case of federal tax credits, you are also financing it and putting the burden on your children in the future.

This is the way it is and I will be taking advantage of these credits if I can.

Return on Investment

If you take a closer look at these incentives you will realize they are very much an artificial stimulus for the various alternative energy suppliers and installers out there. Upon scrutiny you will see commercial providers rarely provide a cost effective solution for their green wannabe customers and, thus, rely on tax credits to help fund their operations. This is a form of corporate welfare. This is not to say the alternative energy industry does not provide good quality products with superb installation… they do. As we will discuss below, most have pricing that, even with incentives, provides a return on investment (ROI) that is beyond ridiculous.

Story time…

Once upon a time in the 1990s I was in Flagstaff, Arizona working with Lowell Observatory on a new telescope installation. I noticed a shop on US66 (yes, the famous Route 66) called “SOLAR ENERGY STORE.” Cool I thought. I made a point to stop by that store during a weekend break because I really was eager to critique the latest solar energy methods available. I walked in the door and what did I see? Wood Stoves… lots and lots of wood stoves. I love wood stoves too, but could not figure out why they were in the SOLAR ENERGY STORE. I asked a salesman where were the solar energy products? He said “We have not had those hear since the 1980s.” I reminded him the name of his store with a clear expectation of an explanation on my face. He said since the Carter tax credits expired in the Reagan years, solar energy was just not viable and not worth selling.

?

I blinked. I paused. “You mean your industry can only survive if subsidized?”

“Yup.”

I believe subsidies should help folks who cannot otherwise afford items get them if the result helps the whole. I do not think they should help prop up an industry that refuses to grow up and produce products that are financially sensible to purchase and use.

So, in the text below, tax credits and other benefits will be ignored and the systems rated for their ROI on their initial costs because it does not matter if the purchase funds are from cash reserves or from our children’s future. Only the selfish would evaluate ROI based on the net cost after rebates are applied. It is up to you ensure tax credits applied to your system return good value for those credits.

Here is the next point. If any equipment vendor suggests a return on investment of more than 3-5 years something is terribly wrong with this picture.

There is an old saying about poker players; If you can’t spot the sucker at the poker table, it is probably you. The same goes here. You should never accept return on investment periods for capital equipment more than five years with three years being more like it. It does not matter if the equipment can and does survive 20 or more years. If you break even just as the equipment’s life ends, who made the profit? Put another way, did the equipment ever save you any money (via reduced energy costs) or did the whole benefit just flow to the organization that sold you the gear by taking all your future savings up front. YOU are the one putting up your hard earned cash so you deserve all or most of the benefit realized from YOUR money. It does not matter where you obtained the cash be it savings, home equity line or other. Somehow or another you executed a financial transaction to get cash in hand. This investment needs to work for you.

You need to understand any business that tries to charge you so much money for an alternative energy system based on a return on investment scaled to most of the lifetime of the equipment is structuring the deal to benefit themselves, not you.

Energy Payback

If you have a little greeny weeny in you, be sure you understand how much energy it took to build, deliver and install the energy system you are planning. Things seem to be headed the right way in this regard, but you need to understand all your best efforts may result in a net energy loss which spoils the whole reason many invest into alternative energy in the first place.

Evaluation Criteria
For this post, the following criteria will be applied…

  • Return on Investment
  • Energy Payback
  • Total System Cost
  • Difficulty of installation

PV Solar Electric

It is no secret the cost of Photo Voltaic Solar Energy systems provide no practical return on investment for the investor. Where traditional energy sources are available, these systems are purely a philanthropic exercise. Vendors suggest ROI periods measured in decades. It amazes me customers with any business savvy whatsoever would accept this ROI from any investment short of, say, a house.

  • Return on Investment – Decades which is hopelessly ridiculous. Ebay seems to have bare PV cells available for about $1/Watt which drastically reduces the installed price to $3/Watt and ROI, but not enough.
  • Energy Payback – One to four years if operated full time… and getting better I sense. The Ebay “seconds” PV cells may eliminate this concern since you are using cells destined for the trash.
  • Total System Cost – $10,000 – $50,000 and maybe more based on about $4/Watt. This assumes you are trying to replace the energy consumption of a typical home. You can scale the size down and realize less benefits. The cost per Watt goes up a bit, but the same ROI issues are true no matter how you scale the system.
  • Difficulty of installation – The concepts are easy to follow, but this is serious electrical work and should only be accomplished by a licensed electrician with knowledge of PV Solar.

Wind Electric

If you have a windy wide open backyard a wind turbine might be sensible. I looked at various DC and AC approaches and find merit in many of them. My favorite wind turbine approach uses higher voltage three phase AC from the turbine all the way to the load point where it is rectified, regulated and applied to the load; The higher voltage requires less copper wire for the same net power transfer. The load can be a battery system and/or a grid tie inverter. The cost per watt are still pretty high at $4/Watt, but plenty of DIY efforts can tame this cost.

  • Return on Investment – Dozens of years unless you put your own time into it and, perhaps, find components on the cheap.
  • Energy Payback – I could not find data on Energy Payback for this approach. Like with PV Solar using slightly cosmetically defective or recycled components may help this greatly.
  • Total System Cost – $1000 will get you started.
  • Difficulty of installation – This depends on your electrical and mechanical capabilities. The AC voltage approach can and does use voltages well above the level than can kill you. A licensed electrician is essential.

Thermal Solar

Using heat from the sun has been around since time began. Nature offers many examples including cold-blooded animals positioning themselves to partake in the morning sun’s heat after a chilly night. Camping equipment vendors offer “Solar Shower” black bags which absorb heat and transfer it to a few gallons of water inside ready for a warm shower later. A good architect will design a house to make good use of Winter’s lower angle solar rays to heat a room with well placed windows and eaves. What the above examples imply is it is not very difficult to make use of free heat from the Sun.

Often the #2 energy hog in a house, the water heater is a logical focus for solar heating.

  • Return on Investment – The Energy Industry seems to have the same game in play where they price their equipment at the level of your eventual savings thereby leaving you will little benefit. Fortunately solar heat collectors can work with low grade heat allowing for ample compromise in collector construction. Plus DIY is alive a well in the thermal solar realm leaving plenty of opportunity for the ambitious handyman. Most thermal solar assemblies rely on a storage tank. Money can be saved if you time your solar install with the end-of-service replacement of your water heater; For a few hundred dollars more, you can get a larger tank with built-in heat transfer coils ready for your later install of the thermal solar panels and associated plumbing (This assumes an indirect thermal system). Thermal Solar Collectors are possible to build at home thanks to their relative simplicity.
  • Energy Payback – The materials needed for thermal collectors seem routine enough to not stress the EP too much. I don’t know the details though. It certainly takes energy to manufacture a decent hot water storage tank. However, as explained in the previous bullet, if you replace an aging water heater you are investing a regular maintenance expense into your system.
  • Total System Cost – The Rheem Solar Water Heating products are north of $800 up to $2000 depending on model. I suspect with panels we are talking $1000-$3000. DIY on the panels can save big.
  • Difficulty of installation – This is a plumbing task and, if you build your own collectors, a carpentry task. It might make good sense to let a plumber do the replacement of your water heater with your solar water heater. This way, you greatly reduce the risk of an incomplete job leaving you are your family without hot water. One important addition to the usual hot water heater connection is a water tempering valve. These are pretty expensive, but required if your solar install is a success as temperatures in the tank will be much hotter than you want for your home’s fixtures. Here again the benefit of a good plumber will make this install neat, tidy and functional.

You may have noticed, in the above words about thermal systems, the idea of replacing your water heater with a new unit rather than adding a thermal storage tank to an existing system. The goal here is to make use of the solar hot water as directly as possible. If you have the classic heat storage tank feeding a traditional water heater, that heater still needs to maintain the temperature of the tank during times of no hot water flow. If you, instead, use the one tank approach, the solar heat is directly heating and maintaining the temperature in that one tank. This maximizes efficiency. Plus the Rheem products have the usual electric back up during very cloudy days or moments of high demand. This important point will ensure your family will never notice a lack of hot water maintaining peace.

Conclusion

Of all the many possible ways of utilizing solar energy, the thermal system provides the best possible return on investment both in energy and dollars.

When you shop for a PV Solar Grid Tie inverter you are well advised to ensure the unit complies not only with UL testing, but also passes some form of Part 15 Class B test.

This gives you the best chance of not corrupting the communication ability of a licensed communications service such as FEMA and even Amateur Radio.

Even with Part 15 compliance there is a bit of risk involved with installing DC to AC inverters as they are inherently very noisy in radio communication bands. The better ones do their job and do it quietly.

It is absolutely possible for your new PV Solar Electric system to fully comply with Part 15 Class B requirements and still cause interference to a licensed communications service. It is up to you, the owner of the Part 15 equipment, to ensure you do not interfere. If you cannot terminate the interference during operation of your equipment you are obligated to cease use of your system as the licensed services have absolute priority.

It is a popular incorrect notion you have a right to operate any product you can legally purchase.

Checkout the language of the FCC’s Part 15 rules to learn more. Part 15 devices may not pollute the RF communication bands under any circumstances. Also they must accept any interference from primary users. Harsh, but true.

Many folks stumble into this issue often with 802.11 wireless LAN sharing bands with other services on a secondary basis.

Anyway, the point is investors of PV Solar are committing vast amounts of cash into their systems and are taking a big risk with the noise from their inverters. You are 100% responsible for any issues so be careful.

This following is a myth.

“JACK/PLUG – In electronics, a jack is a female part into which one inserts a plug, the male part.”

While often the case, the real definition is the jack is the more fixed of a connector pair and the plug is the less fixed connector of the same pair. Where two connectors are neither less or more fixed with respect to each other, both are a plug.

This was quite sensibly defined most recently in the IEEE-200-1975 standard. This standard was renewed in the 1980s and withdrawn in the 1990s. Even so it and IEEE-315-1975 form the basis on how to create reference designators in and around electrical equipment.

The notion Jack and Plug ever meant anything to do with a male or female contact, seems to have come about in the 1980s and 1990s. Somewhere in that time frame young engineers were not properly mentored by their elders in the way of good engineering practices. Bad habits leaked into the general population and now very few technical folks know how to properly annotate the references in harness designs and other electrical assemblies.

IEEE-200-1975 (also known as ANSI Y32.16-1975) serves as the last collection of knowledge dating all the way back to the 1950s in the MIL-STD-16 specification. UPDATE: See Below

Golden rules for harness reference designation from IEEE-200-1975 include:

  • The movable (less fixed) connector of a mating pair shall be designated P [where P means plug].
  • The stationary (more fixed) connector of a mating pair shall be designated J or X [where J means Jack].
  • If two cables are to be connected to each other, each of the mating cable connectors shall be designated P.

That last item is a mind blower for many. Yes this really means there is no such requirement to have J123 connect to P123. Efforts to try and achieve this are a notorious waste of time and such conventions are very easy to violate and, thus, break. A complete system on how to annotate an entire collection of electrical equipment is well defined in IEEE-200-1975. Despite it being withdrawn from active support in the IEEE, copies are still available from Tech Street and other standards suppliers.

Frequently heard statements:

Statement:
“The fixed/less fixed distinction doesn’t work when both are unfixed, as is commonly the case when cables are being extended or split.”

Response:
This was never a problem since Plugs can connect to Plugs.

Statement:
“Whatever IEEE may have wanted to establish, that’s not how it worked out…”

Response:
The IEEE did not establish anything. They documented what was once common knowledge, at least for technical folks, in the 1970s based on documentation dating back to at least the 1950s. It is clear the lack of mentoring is creating the break from tradition.

Statement:
“Plugs always have male contacts while Jacks always have female contacts.”

Response:
No they don’t. Look at any PC (an older one) with a DB25 parallel and DE9 serial ports – all Jacks. Look at the AC power “Jack” on your PC – male for a very good reason. Still other connectors, aerospace connectors come to mind, have both male and female pins in the same body.

Statement:
“Our engineers are from MIT so our custom annotation system is better.”

Response:
Perhaps, but the chance any super star engineer can outwit the collective knowledge of thousands of engineers and hundreds of thousands of man-hours documented in the standards… is laughable. Sure you may have the smartest team on planet Earth. Good for you. Keep their talents focused on the real engineering problems not engineering methods. Otherwise your A-Team will be in the unemployment lines after you miss your deadlines.

Statement:
“We mandate each Pxyz to match up to the same Jxyz.”

Response:
This instantly breaks if you have two identical sub-assemblies in your assembly since each item will have the exact same series of J numbers on its housing. IEEE-200-1975 provides a very simple and elegant solution for this scenario; Buy a copy and read it.

Statement:
“We ensure all the Jacks on all duplicate sub-assemblies are unique by writing new J numbers over top the ones printed by the manufacture.”

You just tripled the paperwork to track the “change” you made to an, otherwise simply identified, off the shelf item and must generate a whole new Control Drawing to track this change. Hopelessly ridiculous.

Statement:
“Do Engineers care about the proper use of reference designators?”

Response:
Engineers care. Engineeer wannabees don’t. Harsh, but true.

Other Standards?
I have searched the standards archives in depth to find any current standard that dictates a better approach than IEEE-200-1975. SAE AS50881 “Wiring Aerospace Vehicle” comes close, but really addresses how to identify the wires bundles themselves, not the connectors. UPDATE: See Below

The point is this. How to properly annotate electrical assemblies is nothing new. At some point the knowledge was dropped and chaos erupted causing, among other things, the bizarre concept of a plug meaning a male.

To Young Engineers:
If you are a young electrical engineer, you need to buy your own copies of IEEE-200-1975, IEEE-315-1975 and why not also IEEE-280-1985. Read them. Learn a great way to annotate. Amaze your boss by saying you will take responsibility for annotating your next project using a real standardized approach rather than home-brewing some half-baked method.

To Supervisors:
Supervisors, you need to find a way to pass on the knowledge stored in the above standards. If you don’t you are literally spending your project funding on the equivalent of learning how to read and write. Keep your engineers focused on the real problems to solve. Don’t spend time re-inventing the wheel.

To Contract and Specification Writers:
Make adherance to IEEE-200-1975 and IEEE-315-1975 a requirement. Save money.

If you do nothing else, please find a copy of IEEE-200-1975 and read it through once. It is very short.

Good luck.

UPDATE July 29, 2009

The commenter below discovered ASME, the mechanical engineering standards group, created a new standard to pick up where the withdrawn IEEE-200-1975 left off. It is called ASME Y14.44-2008. Apparently the void left by the removal of IEEE-200-1975 was felt by many so ASME came to the rescue with ASME Y14.44-2008. How embarrassing for the IEEE to have a mechanical engineering association pick up an electrical equipment standard.

I have ordered a copy from ASME and eagerly await its arrival for review and comparison. Stay tuned to this COSJWT post.

I was talking with a friend of mine who specifies battery technologies for a living. Our conversation drifted to the topic of electric vehicles and, more specifically, the batteries for them.

I suggested the idea that many times the good old lead acid battery is hard to beat for many applications, even ones with severe weight requirements because:

  • Joule for joule they are heavier than newer battery types include Lithium chemistry variants, but they are not an order of magnitude heavier
  • Most everyone knows how to deal with a lead acid battery
  • The recycling process is very mature – at least in the US
  • Within practical limits, lead acid batteries handle over charging
  • Vehicle electrical systems are most often designed with the expectation a lead acid battery is strapped across the bus to help regulate the voltage

My friend added some more thoughts on why it is, perhaps, folly to think Lithium batteries will fulfill the goal of replacing today’s vehicles with all electric versions…

  • There is only so much Lithium in the world
  • There is not enough Lithium to make enough batteries to replace even a fraction of today’s vehicles
  • With a couple of exceptions, Bolivia has a large share of the world’s Lithium reserves and may become the new OPEC leader of Lithium

The particular post came about after reading this interesting article…

Can Better Lead-Acid Batteries Compete in a Lithium-ion World?

…which describes some promising enhancements to the good old lead acid battery.

I wonder if Axion Power is publicly traded…