Direct Methanol Fuel Cells

[Serge]

There is over twice the energy in gasoline as methanol.

True, but volumetric density of Roadster's pack is even lower; it's all about how efficiently the fuel is transformed into energy of motion.

Another reason you don't see to many methanol vehicles, methanol pulls moisture from the air when the container housing it is not completely sealed.
Fuel + water dont mix.

While a bad thing for methanol ICE, water is actually required for reactions to take place in a DMFC.

A minimum requirement of a "range extender" is enough power to maintain highways speeds. I'm not sure if DMFCs are there yet; if they are, then they are potentially a decent range extender.

Indeed. I usually consider sustained 20 kW a minimum requirement for highway travel. I couldn't find any direct confirmation of power density for the latest model being developed by Samsung in conjunction with ViaSpace for the Army. However, earlier prototypes, targeted primarily at portable electronics market, had power output of 20 Watts. The new models supposedly:

generate 54% more power than existing models, and have enhanced durability, up to eight times that of previous models.

This power output level seems to be targeted to a specific application (military). Note, for example, that a common military rechargeable battery BB 2590 has 15 W of power. It also appears that DoD is upping the ante. In 2007 Wearable Power Prize competition the devices had to satisfy the following power/energy requirements properties.

The system will be connected through the single power outlet to standard electronic loads executing a load profile which will be identical for all systems. This load profile will dissipate 1840 W-hr over a 92 hour period. The load profile will include periods that are less than 20W and periods with peak loads that range up to 200W for 5 min. maximum duration. The maximum possible load encountered is 200W for 5 minutes

The winning team's (DuPont/SFC Smart Fuel Cell) DMFC was slightly heavier (3.7 kg) than Samsung's (3.5 kg). Can we assume that Samsung's unit is also capable of delivering 200 W if for a short period of time? If so, what prevents the operation at that power output level for longer periods of time?

[doug]

Stumbled upon this older ABG article,
Will direct methanol fuel cell beat li-ion plug-in hybrids in the long run? - Autoblog Green,

which refers to this piece in the HuffPost from last December (before the Obama administration).
Patrick Takahashi: Is There An Option More Promising Than The Plug-In Electric Vehicle?

The U.S. Department of Energy has prohibited providing funds for vehicular DMFCs, and furthermore, stopped supporting biomass to methanol R&D. It has mostly to do with ethanol and biodiesel being selected as the only national biofuels. Thus, we are probably a decade away, if not longer, from being able to convert to a biomethanol economy for transportation.

[Serge]

Found a German company, named Smart Fuel Cells, which already has commercial offerings.

For example, check out their new product to be released in Oct. (Pro 2200):
Output is 90 W from a 8.8 kg device. Not yet good enough for a highway range-extender (hypothetical 20 kW units weighs a hefty 200 kg), but it's 38% improvement in power output over their current Pro 1600 (65W) model. Since unit weight is roughly similar (8.4 vs 8.8 kg) and fuel consumption is the same (.9 l/kWh), looks like improvement in power output was achieved via higher efficiency.

[Serge]

Stumbled upon this older ABG article,
Will direct methanol fuel cell beat li-ion plug-in hybrids in the long run? - Autoblog Green,

which refers to this piece in the HuffPost from last December (before the Obama administration).
Patrick Takahashi: Is There An Option More Promising Than The Plug-In Electric Vehicle?

I wonder if "prohibition" is indeed in place. DoE's methanol site doesn't have much info, with main future benefit listed as methanol being a potential feedstock for hydrogen production.

[Serge]

One of the drawbacks shared by DMFCs and HFCs is [currently high] use of [very] expensive platinum as catalyst. The other is [relatively] low efficiency.

Apparently, the following research seeks to address both problems at the same time: Carbonized Titanium Dioxide Nanotubes Could Significantly Increase the Efficiency of Methanol Fuel Cells

Currently, methanol oxidation is usually carried out at catalytic electrodes with a carbon support and a platinum or ruthenium catalyst.

Titanium dioxide nanotubes have been under consideration as an alternative to the carbon support for a number of years, but our new conducting oxycarbide beats these by a mile: Supports made of the oxycarbide increase the activity of the catalyst for the methanol oxidation by 700%.

[doug]

This is worth looking at:

http://www.panasonic.com/industrial/...llOverview.pdf

From 2003, perhaps there is an updated version.

[Serge]

This is worth looking at:
http://www.panasonic.com/industrial/...llOverview.pdf
From 2003, perhaps there is an updated version.

Good find, Doug. Presentation, I find, provides good insight into challenges that DMFC technology faces or faced a couple of years ago. I wasn't able to find an updated presentation, but the latest mention of Panasonic's DMFC development is this 2008 article. It looks like volumetric density comparable to Li-Ion battery has been achieved, indicating that Panasonic is at the tail end of Phase I (according to chart on pg.15)

Nice to actually see a list of technical breakthroughs required for Stage 2 commercialization, which I understand would be a roll out of first commercial product:

1. Power density needs to be greatly increased:
   
   • Membrane: Reduce methanol crossover. Looks like some work is covered in Matsushita Technical Journal, Aug. 2006
   • Catalyst: Platinum-free catalysts mentioned earlier. Recent research into high efficiency platinum alloys.
2. Energy density needs to be greatly increased:
   
   • Miniaturization: Prototype from last year shows they are are making progress on this goal.
   • Increase methanol concentration: An Upstate NY company called MTI Micro developed a DMFC called Mobion running on 100% methanol. Supposedly, their parent company has cash problems . Interestingly, they are collaborating with Samsung.
   • By the way, does anyone understand Japanese and could translate data elements in this chart?
     
     It came from another Matsushita Technical Journal Jul 2006 issue mentioning DMFCs

[doug]

1. 
   
   • By the way, does anyone understand Japanese and could translate data elements in this chart?
     
   
   

Yes, the x-axis is year, y-axis says energy density. The inset key from top to bottom says: 2nd generation lithium ion battery, 1st generation lithium ion battery, nickel metal hydride battery, nickel cadmium battery.
(fyi: the non-Chinese characters are actually phonetic English. enerugii, richiumu ion, nikkeru kadomiumu...)

[Serge]

Yes, the x-axis is year, y-axis says energy density. The inset key from top to bottom says: 2nd generation lithium ion battery, 1st generation lithium ion battery, nickel metal hydride battery, nickel cadmium battery.
(fyi: the non-Chinese characters are actually phonetic English. enerugii, richiumu ion, nikkeru kadomiumu...)

Cool, Doug! I thought the first line was DMFC. I wonder now what is this 2nd generation li-ion battery (>600 Wh/L) and is that's what's in the Roadster?

BTW, I tried real hard, but didn't see any "non-Chinese characters;" all look like hieroglyphs to me.

[doug]

KDDI Shows Latest Prototype Phone Based on Fuel Cell - PC World