Lithium Ion Battery Range Poll

[ryan.brandys]

We are looking at supplying managed lithium battery packs to the EV hobbyist. Please select the battery pack range and price you'd most be interested in.

[nathan.stowe]

I am holding out for Li to be about 5k for 30-40 miles range.   I had worked out a deal which was just a bit more expensive than this from thunder sky, but given their bad track record and that this is my first attempt at an EV, I decided to go with the tried and true PbA for now.  Then when those are dead, see what is offered.

[ricky.hazen]

With my daily commute being 60 miles (30 each way & if we ignore the cost of conversion) I would feel -
Rather uncomfortable with the 40-60 pkg.
A little more comfortable for a period of time with 60-80 pkg.
A lot more comfortable with the 120-150 range.
BBBBBBut - at the moment I'm still in the ICE age & at current prices = many tanks of pertol . . . . . . 

[larry.backes]

Like Nathan, I voted for none of these because I will wait until the price comes down further to purchase.  $8K for 100 miles.

[geoffrey.pullinger]

I guess I should have asked how many charging cycles at 80% DOD are lithium batteries capable of.  The knee jerk reaction is to say no or none when you look at the prices (I did).  However if they are capable of 1,500 to 2,000 cycles vs 300 or 400 for lead acid batteries then the lithium batteries could actually be cheaper  - as long as you don't wreck your EV in the first 60,000 miles or so. 

[todd.dore]

One very important thing that you must remember - the LiIon batteries need a Battery Management System for EACH cell - that is, something that can regulate both input charging current and output discharging current.  To my knowledge, there isn't any home-grown BMS (or LiIon batteries, for that matter) that I have heard of in a full street-legal EV (capable of highway speeds) in the entire midwestern United States.

Without the proper BMS, the batteries don't last anywhere near 2,000-3,000 cycles, and depending on the chemistry they may catch fire.  So the BMS is critical.

Due to this very practical limitation, LiIon batteries have not been used by EVers and in my opinion will not be used very much (if at all) in the next 10 years.

In 2003 we were hoping (and fully believed) that LiIon batteries would come down in price.  They have not - they have only gone up in price, due to general surging demand in lithium batteries from China and India, along with the decline of the US $.

My prediction is that in another 5-10 years the prices will not come down due to volume production and may actually continue to climb.  A good example is NiMh batteries - they make millioins of packs for all the hybrids, but none are available for the hobbyist EVers.

Let's stick with lead-acid and learn to live with 20-50 miles on a charge.  It's called planning your trip, pushing hard to opportunity charge whenever you can, and CONSERVE, CONSERVE, CONSERVE.  It's the only way a daily use EV will meet your needs.  Think of it as being ahead of the curve - in 10-20 years, oil depletion will force everyone to conserve - so we're doing it a couple decades ahead of time, and helping out the environment and using a little less foreign oil to boot.

[geoffrey.pullinger]

Possibly we are expecting too much when we convert gas powered vehicles to EV's and want them to behave like the gas powered version.  A paradigm shift is probably coming where daily transportation has a more tiered structure.  Electric car to do local shopping etc. bus or train to work and other distant locales - no gas car - unless you are extremely wealthy and want to pay $200.00 a gallon.

[ryan.brandys]

One very important thing that you must remember - the LiIon batteries need a Battery Management System for EACH cell - that is, something that can regulate both input charging current and output discharging current.  To my knowledge, there isn't any home-grown BMS (or LiIon batteries, for that matter) that I have heard of in a full street-legal EV (capable of highway speeds) in the entire midwestern United States.

Todd,

You're absolutely right that keeping the lithium cells balanced is critical. When I purchased 6 kWh of Thundersky LiFO4 six months ago, I decided to design and build my own BMS for the lithium cells. I installed the managed lithium packs into my pure EV DeLorean, and now drive it around on a daily basis. It can even go on the highway. When you plug it in, the BMS rebalances the cells and polishes them based on current and voltage, not voltage alone.

Thundersky remains the only lithium cells that are DOT approved for use in vehicles. Now I'm looking at packaging Thundersky cells into managed lithium packs and offering them to the EV hobbyist.

I also don't think price on lithium will come down substantially any time soon. Instead, I think energy storage capacities will improve as the new chemistries currently being researched become more common.

-RB-

[todd.dore]

Ryan -

If your LiIon pack is working, then I stand corrected.  You may be the first.  How about bringing the pure EV Delorean to the next meeting for us all to see?

I roughly estimate that you can get 10-15 mi. on a charge (with a 6kWh pack - which is relatively small).  Is that what you are seeing?

Also, do you have an estimate as if and when you would sell your packs w/BMS to other EV hobbyists?  When the time is right (not now) I could be ready to purchase one, but I would want at least a 15kWh pack (and perhaps a bit larger).

-Todd

[ted.lowe]

Great Ryan!  Could you quote $/kWH instead of $/miles range (the latter would vary by vehicle).  Also, what is the expected lifecycle of the TS's ?  Finally, i assume these prices include your BMS for the whole pack?  Thanks!

[lawrence.miller]

I am considering converting my Prius to Plug-in in the distant future, depending on the gasoline prices. The 20-30 mile range meets my needs, ~10 kWh. For the price listed of $ 8,000.00 and assuming 3,000 charge-discharge cycles, it starts to look financially responsible. I will only accept Li cells that do not catch fire and mounted in a fire proof or resistant box, sheet metal may be sufficient.