Battery tech

Battery tech

Hello all.

Just read from autobloggreen about some new battery manufacturer called "Planar Energy". (

They seem to have tech for pretty good Wh/kg batteries. From one of their pdf (

"One of them combines lithium manganese oxide with other ions, and operates at about three to five volts with a charge capacity of 200 milliamp hours per gram."

Calculating that as 3.5V * 200mAh/g you get 700mWh/g or 700Wh/kg. to put that in right context: Roadster battery: 450kg. Drop 30% off as supporting structure: 315kg battery * 700 = 220.500kWh battery. Nearly four times as much as current tech is. That would allow roadster to go 200 * 4 = 800 miles with one charge.

ruslanav | 2010年7月28日

let's do it

taximan53 | 2010年7月28日

I wonder if Tesla would be interested in an idea that would, Absolutely guarantee, that Tesla would be around for twenty years. People would choose Tesla over any other brand. At least until the other brands caught up. And the idea would mean the end of Petroleum as the basis for propelling vehicles. Tesla could do for the automotive industry, what cell phones did for the communication industry. (

Brian H | 2010年7月30日

You'll have to engineer your own direct contact with TeslaMotors. The previous forums were frequented by all sorts of people with brilliant ideas for them, which generally turned out to be unphysical ideas for free energy or the like. AKA loons.

Thx; another multiplier for LiIon tech! And here's a report on the use of graphene within batteries to expedite ion and current movement:

BTW, really hate the loss of all the tech refs etc. embedded in the previous fora. The new broom has been altogether too sweeping, IMO.

zaccman | 2010年7月30日

I would like to see Tesla help drive forward battery technology for electric vehichles by combining the best available technologies to extend the distance and minimize charging time which are both perceived drawbacks to EV's. To this end I submit two weblinks of technologies that appear ready for prime time. #1 nanowire technology to provide 10x the current from existing lithium batteries. I have read that there are several factories already pruducing this breakthrough in Michigan & China and that BMW Mini has already contracted to use them. #2 the use of super capacitors to better power manage sudden acceleration which drains most batteries and better recover energy in egenerative braking systems. I realize tesla is not a battery manufacturer but technologies appear to be off the shelf and ready for prime time. Why not use them now?

untesla | 2010年7月31日

I have heard that these batteries give off dangerously hight EMF radiation and wondered if anyone knew or has tested the levels of TESLA's car batteries.....also, could a lead barrier or casing be made to protect passengers from long term exposure?

untesla | 2010年7月31日

how long does it take for approval of a thread reply?

Straight Shooter | 2010年8月3日

Tesla needs to permanently alleviate all these battery fears that people love to disseminate. The big fear is that as soon as you pay $20k-$35k for your battery, something 3x better will come out next year.

Tesla needs to release a "Battery Mission Statement" that reads something like this......All new Tesla batteries will fit into the existing vehicles. All new Tesla batteries will be offered to existing customers with older batteries or batteries with smaller capacities for a substantially reduced upgrade charge, based on the age and condition of them. A nice graph showing the exact amounts would be easy too, as they don't really have too many different batteries to begin with.

Who really cares what battey makers do? I'm covered!!!!

Douglas3 | 2010年8月3日

untesla, batteries cannot produce EMF radiation. They only produce a static DC potential.

Of course the car's power electronics, like any electronic gadget, will generate electromagnetic fields at some level. That said, the car isn't a microwave oven! It's not going to produce anything even remotely hazardous.

kumar5750 | 2010年8月5日

Hi guys,


kumar palani,
go green.

KGB | 2010年8月5日


I'm sorry, but your idea reminds me of cartoons I used to watch. A character would be in a sailboat, and he would get the boat to move forward by blowing onto the sail. In real world physics, that doesn't work.

My suspicion is that your turbine will add to the wind resistance of your vehicle. So you will only be capturing the energy you lose from the increased wind resistance.

Douglas3 | 2010年8月5日

kumar5750, that's called a "perpetual motion machine", which violates the known laws of physics.

ChadS | 2010年8月6日

untesla, the EMF has been measured in a Roadster. I don't remember the exact number, but it was way less than many common household appliances.

interested1 | 2010年8月8日

I couldn't get the button to work to create a new topic, but I have a thought on charging. We have all heard about the challenges of persons living in multi-use buildings (apartments, condos, lofts, etc.) without garages or without electric in their parking garage. I'm one of those people, but I'm not an engineer. So I don't know if this is even possible, but what if there were a portable charger? I'm thinking of something that is the size of a briefcase that would detach when the vehicle is not in use. It could be taken inside a person's home, office, hotel, or wherever else there is an available 110V connection (or whatever is standard in your country). It would be charged, then reconnected to the vehicle for more driving. Or, it could be 2 "briefcase batteries" and a person would need to charge 1 for x number of miles or both for 2x number of miles.

Just a thought... again, I'm not sure if this is even possible.

Brian H | 2010年8月11日


skipwkk | 2010年8月14日

When is Tesla going to switch to large format batteries ?
I would hope they are working up proto types ask we speak.
I can't believe having 6700+ batteries to manage is the proper way to go (KISS).

Brian H | 2010年8月15日

You may be right, but the upside to small units is that a failure of one has a tiny effect.

Brian H | 2010年8月16日

Slightly OT, but the "New Topic" function is busted:

SF is putting up some free charging posts around the city. Don't know if it's just civic promotion, or a clean air initiative.

John Charles | 2010年8月19日

fnfargento, more batteries is not the answer. Batteries = weight. Weight is the enemy of performance.

Brian H | 2010年8月20日

He's way more confused than that. He wants to charge Battery B while running on Battery A, and vice versa, using the motor as a generator. One more free energy loon.

daryltrinh | 2010年8月24日

Kumar's idea of a wind turbine on vehicles isn't terrible.
We currently use wind to cool radiators
but what about the stronger forces of wind our cars come in contact with when we're driving at high speeds?
Seems wasted that we're not using the force to 'drive' auxiliary motors.
One problem I see is the price per output efficieny.
You'll have to consider the aggregate output of X number of installed turbines and the price.

Overall, what does Tesla think?

trydesky | 2010年8月24日

Isn't Telsa's goal to make there cars the air goes around the car? The last thing you want to do is "catch" the wind.
Combine the added weight of a wind turbine, and the losses associated with wind resistance, and I'm sure it equals a net loss.

Dan5 | 2010年8月25日

The wind turbine idea is thinking outside of the box, but unfortunately, it's a perpetual motion machine and will not work. You still have resistance losses from the wind, at most it will not do anything, and at worst will decrease the range dramatically.

What we could do is place wind turbines on major highways or other busy roads on the side of the road so the draft of the cars and trucks move the turbines. Possibly use the helix turbines since they thrive in turbulent conditions

In theory if it could be coupled with wireless energy transfer (one of the inventions the original Nikola Tesla worked on, and i believe Intel managed to get 75% efficiency in 2009), that could solve the problem- not really "free energy", just recovering waste energy and sending it back to the cars or grid. Unfortunately wireless energy transfer is still in its infancy, so the most viable option would be to send it back to the grid

rodrigocespedess | 2010年8月25日

Hello, long time since I follow their progress online and I can only congratulate him on his initiative and effort they have made to get where they are, because I suppose they had to overcome many pitfalls of the most diverse nature. But my statement is just to ask why the S model is not added a solar panel, however small, not to move the car, but to enhance the autonomy and "never reach zero charge", although it is a wonder car, just 45 minutes to 3 hrs. is a really long time if we consider that to fill a pond are 10 '. So while we wait 45 minutes, at least we know that we charge for many miles.

rodrigocespedess | 2010年8月25日

Sorry, but its theme is exciting, what do you think the use of piezoelectric ceramics in suspension?

DanAderhold | 2010年8月26日

Efficiency is more then just battery technology, some years ago I invented an electronic circuit to measure electrical signal ratios, later patent. One application of this technology was traction control, with respect to drive and driven, as in wheel contact to road or stator and field of electric motor. In either case, traction is the unity between the drive and driven. Efficiency is the measure of power applied versus energy required, and achieved through modulation, and prolonged by regenerative power. All factors contribute to efficiency and include weight, aerodynamics, traction efficiency, battery capacity, and regenerative power.

Brian H | 2010年8月27日

No, all day with the whole roof as a solar collector would only provide a few miles. It's costly and pointless.

Brian H | 2010年8月27日

Here's a new one: virus cathodes, with 10X the capacity of graphite ones.

DanAderhold | 2010年8月28日

Option for regenerative power application,

There are various methods to increase efficiency, one alternative is to separate the power sources used by motor/drive and standard systems. Many standard systems used in common automobiles and trucks operate from 12VDC sources, and include lighting both interior and exterior, instrumentation, power seating, radio, heat and cool, amongst others. An alternative is having two power sources, one primary for motor/drive and secondary for standard systems. These standard systems can operate from Generator and 12VDC supply, and under certain conditions battery charged using solar energy as well. This can be implemented by operating standard systems from primary battery until vehicles forward motion is constant (highway and other), once controller senses this condition, it can electrically switch standard systems to Generator and 12VDC source. The Generator, (somewhat like alternator) can be coupled to rotating shaft or built within wheel for charging battery and power to standard systems. Solar Cell Roof can be applied as another source for charging the 12VDC battery given certain conditions. It’s feasible with smaller battery, the standard systems can be switched from primary to secondary whenever power level is adequate, controller seeks best solution. There’s more detail then stated above, this is basic description. I would implement a permanent magnet generator using one or more wheels, to reduce frictional components.

Timo | 2010年8月29日

@DanAderhold; your proposition to drive ancillary systems with generator just causes more losses than driving them directly from battery pack.

Now: battery -> motor & ancillary systems
Your: battery -> motor -> generator -> ancillary systems.

With every conversion there are losses. Your suggestion added one conversion and energy still comes from same battery pack. And your system would affect car performance because that generator would work as brake that switches on and off without driver knowing when that happens.

DanAderhold | 2010年8月29日

Brian H,

That’s an interesting article, as for developing automotive frameworks into battery platforms. This would disperse cell area more equal amongst the chassis and frameworks, and suspect technology feasible in near future. Maybe application is chassis and framework for battery platform, and body as energy collector. But electric motor technology needs improved as well, applying superconductive materials to reduce size and minimize thermal loses, for equal magnetic drive distribution.

I am saying something without giving details, and it's difficult at times.

Timo | 2010年8月30日

@DanAderhold; electric motors already have 95%+ efficiency, which is one of the highest energy transformation efficiencies humankind have managed to make. It can be made even better, but you wouldn't get much improvement no matter what you do because you can't get over 100% efficiency. So keeping the cost (and complexity) down is priority there.

Now if someone could invent an electric motor that doesn't lose torque with RPM increase _that_ would be real invention. You would get the real "Horsepower" out of the engine (IE. max torque at any RPM would stop you from accelerating only when car losses exceeds torque output and you would get the HP at max torque).

I don't see any physical reason why such engine cannot be made. Horsepower is not real power because RPM is not a force just angular speed measurement, it doesn't really tell you anything, not even top speed because that depends of the car losses. Torque is a real power, and that determines the force that accelerates the car.

DanAderhold | 2010年8月30日

I would disagree, your assumption is generators are the same, and require electrical power to drive at all times, and is wrong, only require forward motion. The generator would not turn “ON” and “OFF”, and would always rotate when vehicle is in motion. With correct generator configuration, magnetic shear would be quite minimal. You maybe assuming there would be frictional lose and that isn’t true either. There are configurations that have “NO” frictional components. Your suggesting there’s no way of regenerating power while vehicles in motion, that’s simply not true. Smaller battery units can be charged using vehicle forward motion, with generator and solar cells.

Load is depleted faster through higher current demand, you know this. It is not proportional.

Brian H | 2010年8月30日

You're saying you want free energy, whether you know it or not. There Ain't No Such Thing As A Free Lunch. (TANSTAAFL) Or free erg.

Timo | 2010年8月31日


Magnetic or no magnetic, if you extract energy from kinetic energy (movement) you slow down that movement at the equal amount of the power you drain from it + losses. There is no escape from that law of physics. Motor turned to generator is a brake. Even zero-weight, frictionless generator would be a brake. Even if there is no losses in that generator, only that brake-part, you have the main engine losses to deal with.

Adding an generator you add an brake to the system and you same time add all the losses that transformation includes. It is much better to use battery directly.

DanAderhold | 2010年8月31日

Tesla - No need to be concerned that am former GM Engineer, I have watched your company grow for some time. I am a big supporter, one that would assist you, whether paid or not.




Let’s make sure the word gets out for all associated technologies.

DanAderhold | 2010年8月31日

Brian H,

I am not talking about Free Energy, that's a catch phrase. I’ve been around too long, try energy distribution with respect to loads. I know Tesla Advanced Technology is impressive, I admire this company more then you think. I have worked with engineering teams for many years, my job was to take, “What many believed wasn’t possible, and make it possible”. And well aware this is what Tesla accomplished. I worked in Asia for a number of years, vision systems using laser and HS camera technology. One task was to improve 95% detection to 100%, many believed this wasn’t possible, but it was systematically accomplished with advanced thinking and new theories.

I am not going to discuss technical detail in these sections. Free Energy, don’t make me laugh, nothing is free!

DanAderhold | 2010年8月31日

There are other factors besides kinetic energy, and you’re aware. In terms of systems and so forth, this isn’t the appropriate format to discuss engineering concepts. I prefer to promote these technologies, and good CRM always helps.

DanAderhold | 2010年8月31日

Brian H,

Sorry I don’t believe in “Free Energy”,
Timo and I were discussing loading versus chemical decomposition. And of course am joking, good luck to all.

DanAderhold | 2010年9月8日

Regenerative power is created when motion or energy loses generated by the vehicle are converted into reusable power. As someone stated, “By extracting kinetic energy you slow down movement by the equal amount of power you drain” and true, but power and efficiency must be considered. In an idea application there are no loses, but in real applications there’s always loses. An example, a person pushes the accelerator and consumes power, and thereafter pushes the brake. The reason, too much kinetic energy was created, so driver slowed down the vehicle. This action resulted in power lose; because brake energy was used to absorb kinetic energy created by the motor. The indicator of this inefficiency was the intermediate braking used to reduce the kinetic energy and slow the vehicle. Regenerative power is realized when this response is sensed as a potential energy lose, and system applied to collect this energy and convert to power and store for use on demand. A vehicle applying regenerative sensing and energy collecting is complex, but feasible.

The ideal transportation system can start, accelerate, travel at constant speed, decelerate, and stop when traveling from location (A) to destination (B). However automobiles often continuously stop, start, accelerate, and decelerate at various locations from (A) to destination (B). In some cases a constant speed can be maintained from location (A) to destination (B), but in rare cases. So it’s important to increase vehicle efficiency when possible, because infrastructure isn’t that efficient. And it’s not uncommon to examine various possibilities of converting inefficient energy use to efficient use.

One method is accomplished by applying traction control technology, and improving efficiency by regulating the power used to achieve forward or reverse motion with minimal slippage. Other research is performed for other applications, to increase driving distance, and for extending the life span of batteries.

A power factor can be measured from the distance traveled (start to stop), because power isn’t constantly consumed to maintain forward motion. This power factor is related to the efficiency of energy consumption to achieve the motion, versus the energy consumed to reduce or counter the motion. One method of increasing the vehicles efficiency is to convert some forward motions (kinetic energy) into regenerative power, or some energy will be depleted through counter motion (braking energy loses). In some cases when vehicle is accelerating with minimal or no current load to motor, the acceleration component (kinetic energy) can be converted into electrical energy using a generator. Regenerative power is achieved by first detecting “potential energy loses” and then converting this energy into electrical. An example, the driver pushes the accelerator and thereafter releases and taps on brake, at this moment the generator coil is engaged to collect energy, and disengaged when accelerator is depressed again. When the driver releases the accelerator, and taps on brake, this indicates too much kinetic energy was created. And for those concerned with continuous magnetic braking, the coil is extended or retracted depending on controller and sensing of regenerative power potential. This application is feasible by using a permanent magnetic generator inside one or more wheels of the vehicle. With the purpose of charging a smaller battery source used to supply power to the standard systems located on the vehicle. Like lighting, both interior and exterior, radio, power seating, wipers, air, amongst other.

Regenerative power systems can be developed with intelligent algorithms, to sense potential energy sources, and engage, collect, and disengage. As stated above, by extending and retracting the coil, the program logic would measure the power applied versus forward motion, with ability to engage and disengage. A solar roof would also be used to charge smaller battery as well, so there are several sources for recharging. The solar cell is feasible when the power source (battery) is smaller. If the smaller battery had insufficient charge, the secondary systems can be electrically connected back to primary power source.

The affects of current loading on battery are, (1) Higher load currents create thermal energy that requires battery cooling. (2) As current increases, more energy is required to cool battery, and therefore more power. If the thermal energy is not converted into power, it’s an energy lose. (3) Higher load currents increase the rate of discharge and shorten drive time. (4) Higher load currents increase the rate of chemical decomposition, and thus shorten life span of battery.

Therefore adding a generator and small battery that’s configured correctly will add value to the system, in many ways. The added weight isn’t significant, less then 50 lbs at most, versus each passenger at about 150-175.

Timo | 2010年9月8日


Couple of comments:

1) generator placing in tires is a safety hazard, unless you counter its braking effect by braking other tires as well (car balance), therefore losing energy.

2) I very much doubt that adding extra battery with extra generator with associated electronics would be any more efficient than motor used as generator even when used only when vehicle is slowing down.

Also that cannot be used when traveling far, because in that case you are either doubling the losses for those ancillaries or you lose them. In those conditions car needs to use energy to sustain movement and you can't use generator without doubling the losses.

In any case even if you could get something out of this the difference would be so minimal that added weight, complexity and cost would probably be better used to just install a bit bigger battery instead.

DanAderhold | 2010年9月8日


You’re made some good points,

1) Yes, the best solution is using two generators to balance vehicle, even though magnetic shear would be minimal. These generators should be in phase with drive motor, due to regenerative braking from drive motor.

2) As you know some motors can be used as generators, however most are not designed for this use. The reason for various motor and generator designs is due to application versus efficiency. A motor can have high efficiency rating when used as motor, but low efficiency when used as generator.

3) The efficiency of system is observed by use of power, and whether or not potential loses can be converted into energy for regenerative power. Regenerative power relates to generators in wheels, used when potential energy loses are detected, the use of thermal energy TE Technology, and alternative sources such as solar roof. So idea is to evaluate potential loses and ways and means of compensating to increase power efficiency.

DanAderhold | 2010年9月11日

Brian H and Timo,

Farewell, and good luck..

xbaddie | 2010年9月12日
Dan5 | 2010年9月12日

The microbial fuel cell part seems very similar to what I did back in college. There are alot of issues with microbial fuel cells.
Typically, you use something like yeast, methylene blue (electron stripper), and ferrous II cyanide separated by a naphion membrane. Biological fuel cells are a good idea, but in practice, getting them to work long term is rather difficult.

1. They are VERY sensitive to temperature (rule of thumb is for every 10 degree C, double the microbes biological rate)
2. If it's a photosynthetic bacteria, you need sunlight and water, if not, you need another fuel source (typically polysaccharides along with other materials)
3. I know when I was working on them about 8 years ago, the cell life expectancy was on the order of a 1 week or less, either the microbes ran out of food, the yeast clogged up the cell, the anode degraded, or the yeast died due to the fuel cell "stealing their energy"

gmackin | 2010年9月23日

It seems that currently the biggest drawback to EV is range/recharging. Sounds crazy but the addition of a gas generator onboard could extend the range considerably. A 27 lb generator,converted to Liquid Propane Gas (LPG) could produce 1,000 watts/120 volts for hours depending on the size of the LPG tank. The tank and generator could be placed underneath and in the middle of the vehicle for safety.I know this is not ideal, but until battery technology/life improves, this technology is here today. LPG is very low in carbon emissions, is more prevalent than E-85 or electric outlets. At 20 feet away, the generator emits 47-57 decibels, which could be greatly reduced with an exhaust system.

Steve | 2010年9月23日

gmackin: A 1kW generator would be useless, just like charging from 120V is mostly useless unless you can leave the car to charge over a day or two. It takes about 15kW for highway cruising.

EVTom_Norway | 2010年9月23日

"It seems that currently the biggest drawback to EV is range/recharging."

Only to non-EVers. My EV charges while I sleep and I start every day with a 'full tank'. My present EV, 2000 model Th!nk City, has sufficient range - 60 miles - for a day's driving.

Nicola | 2010年9月27日

I remember Elon once talking about riding the wave of battery development. Here comes the next wave: A Li-Ni battery with a massive energy density, which would bump the range to 700 miles. Is this what you were referring to in your original post, Timo? It's Still in the development phase, so probably not out in time for the first S, but maybe by 2014 or so... Tesla, are you working on this new battery tech at all? Here's the article:

If the fragile glass membrane is the issue, could it be reinforced with carbon, or a membrane like safety glass? Industrial ceramic?

Nicola | 2010年9月27日

Here's another interesting Technology - using nanoparticles to generate electricity from waste heat. Still very experimental.

Timo | 2010年9月27日

No, that's not the one. full text has this:

"Then a practical energy density near 428 Wh/kg can be expected for this cell chemistry."

That battery I was referring to is was Planar Energy battery with more traditional chemistry.

What I referred was guessed Wh/kg from chemistry alone. Someone from Planar energy mentioned this in comment section of Technology Review -page:

"The design point for the prototype Planar cell, fully packaged, with a capacity of 5 Ah, is a specific energy of a little over 400 Wh/kg. The energy density of this cell is a little over 1200 Wh/l. Larger cells will yield numbers that are improved a bit. "

So, not quite that good, but thing is that this is already in prototype-phase and that volumetric energy density is really good. 90+kWh battery would be only 75L in size. Small size helps to position it easily into BEV. Also it would weight (without supporting structures) only 225kg, which is about half of what Roadster battery weights now. Less weight = better performance + less rolling resistance = bigger range/kwh.