Interesting post on Tesla design flaw... - Page 2 - LotusTalk - The Lotus Cars Community
LinkBack Thread Tools Display Modes
post #21 of 23 (permalink) Old 01-05-2009, 04:43 PM
Registered User
Join Date: Oct 2003
Location: Bedford, NY
Posts: 6,301
Is that their "unique safety technology"?

Tesla Motors, Inc., the US venture business developing electric cars, is fitting its "Tesla Roadster" model electric cars, which began commercial production in March 2008, with 18650-type Li-ion (lithium-ion) batteries, which are widely used in standard consumer electronic products. These are ordinary lithium-ion batteries, with dimensions of 18mm diameter and 65mm length. Tesla Motors has incorporated its own unique safety technology into these lithium-ion battery cells, and is now fitting its Tesla Roadster vehicles with the proprietary car battery pack containing 6,831 battery cells.

  Usually, car battery packs might only contain around several dozen cells that have been developed for automotive-use. For example, the Mitsubishi Motors Corporation "iMiEV" (Mitsubishi innovative Electric Vehicle), scheduled for commercial production in 2009, is fitted with a lithium-ion battery pack containing just 88 rectangular-shaped lithium-ion battery cells, with each cell having dimensions of 113.5mm 43.8mm 171mm. In comparison to the iMiEV, the Tesla Roadster's car battery pack consists of smaller dimensions and a much higher number of cells.

 The Tesla Roadster is a sports car developed with the affluent consumer in mind. It has great acceleration performance, going from zero to 100km/h(62mph) in just 4 seconds. Each battery charge delivers enough power to travel approximately 350km, which although seemingly short of travel distance of gasoline-powered vehicles, is still sufficiently practical. (it is worthwhile noting that the batteries themselves are heavy: with the battery pack occupying approximately 40% of the gross vehicle weight, or 450kg of the vehicle's gross 1125kg.)

 The White Paper accessible from the Tesla Motors website reveals the reasons behind its decision to use standard 18650-type lithium-ion batteries, which are commonly used in consumer electronic products. Some of the reasons noted included being able to draw on advances in technology developed for lithium-ion batteries for consumer electronics over the past 15 years. This has led to success in keeping costs down whilst simultaneously improving energy density. Furthermore, the small cell size means that the amount of energy per cell is also small, and in the event that a single cell should suffer a defect, the overall impact will be much less than in the case of a defect occurring in a much larger battery cell. In addition, several billion 18650-type cells are manufactured each year, and these are also becoming safer year by year. In selecting battery manufacturers, Tesla Motors only considered reputable companies that had actively invested money and resources to minimize manufacturing defects within their cells.

  In comparison to regular consumer electronic products, the usage conditions imposed on batteries for automotive-use are much stricter. For example, while regular batteries only need to be guaranteed to operate under temperatures between 0 and 70degrees C (32 to 158 degrees F), the corresponding range demanded for automotive-use battery is from -40 to +85 degrees C (-40 to 185 degrees F). It is interesting to note that although Tesla Motors has incorporated its own unique safety technology into its cells and battery packs it adopts the widely-used 18650-type commodity cells. We look forward to monitoring further developments in the future.

2011 M3 convertible

Previous car #2 - 2008 Elise SC Ardent Red - Touring, Sport, Starshield (found a new home)

Previous car #1 - 2005 Elise Saffron Yellow (totaled in flood- the original underwater elise)
ivan1 is offline  
Sponsored Links
post #22 of 23 (permalink) Old 01-05-2009, 05:34 PM
Registered User
smicker's Avatar
Join Date: Mar 2006
Location: Alameda, CA
Posts: 557
Originally Posted by rob13572468 View Post
...tesla has people who are paid to come on this forum and cheerlead for them when there are obvious glaring problems.
Methinks you way overestimate Lotustalk's signal on Tesla's radar
smicker is offline  
post #23 of 23 (permalink) Old 01-05-2009, 08:11 PM
Registered User
vfx's Avatar
Join Date: Dec 2008
Posts: 33
At this point he only Tesla stores are in LA and SF with 5 or so more coming this year.

Agreed it would be difficult being an early adopter of a car with entirely new technology. You can't even take it to a grizzled mechanic but it should be mentioned that the motor has one moving part and the car's first service is at 1000 miles.
A Lotus mech. could probably handle the undercarrige but there are thousand of other things that could fail.
vfx is offline  
Sponsored Links

  LotusTalk - The Lotus Cars Community > Lotus Discussions > Electric Avenue- Tesla, ZAP, Dodge EV1, electric Lotus cars

Quick Reply

Register Now

In order to be able to post messages on the LotusTalk - The Lotus Cars Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome