Posted by Tomes on April 2, 2008, 1:53 am
"bob" ...
> when will this technology be in the new ones?
> will you be able to use lithium ion batteries as replacements for the ni
> mh currently in them?
There is no need to replace the batteries. They have not been failing in
any manner of significant numbers at all.
Tomes
Posted by e on April 2, 2008, 3:39 pm
Tomes wrote:
> "bob" ...
>> when will this technology be in the new ones?
>>
>> will you be able to use lithium ion batteries as replacements for the
>> ni mh currently in them?
>>
> There is no need to replace the batteries. They have not been failing
> in any manner of significant numbers at all.
> Tomes
It's not because of failures... these are reliable
battery packs.
NiMH can be replaced by Lithium-based batteries of the
same weight to produce higher capacity and therefore
longer drive times. Fewer cells are required, as each
NiMH cell is 1.2V while each Li cell might be 3.7V
(depending on chemistry), with similar current density
(amps per unit weight).
One major issue is safety. With a laptop, temperatures
are reasonably controllable. In a car, however, the
temperature range can be extreme. Everyone working on
hybrid and electric cars is focused on this, and it IS
being solved.
I've been considering one of the lithium battery kits
for my '04 Prius, but it runs so well that it doesn't
make sense to experiment with it. Instead, I'll give it
to one of my kids when the HOV lane sticker runs out and
buy a lithium battery Prius (hopefully plug-in!) to
replace it.
Since much of the grid energy derives from coal, hydro,
and nuclear sources, plug-in is a great way to clip the
petro umbilical and stop writing checks to people who
hate us.
Ike
Posted by bob on April 3, 2008, 12:26 am
> Tomes wrote:
>> "bob" ...
>>> when will this technology be in the new ones?
>>>
>>> will you be able to use lithium ion batteries as replacements for the ni
>>> mh currently in them?
>>>
>> There is no need to replace the batteries. They have not been failing in
>> any manner of significant numbers at all.
>> Tomes
> It's not because of failures... these are reliable battery packs.
> NiMH can be replaced by Lithium-based batteries of the same weight to
> produce higher capacity and therefore longer drive times. Fewer cells are
> required, as each NiMH cell is 1.2V while each Li cell might be 3.7V
> (depending on chemistry), with similar current density (amps per unit
> weight).
> One major issue is safety. With a laptop, temperatures are reasonably
> controllable. In a car, however, the temperature range can be extreme.
> Everyone working on hybrid and electric cars is focused on this, and it IS
> being solved.
> I've been considering one of the lithium battery kits for my '04 Prius,
> but it runs so well that it doesn't make sense to experiment with it.
> Instead, I'll give it to one of my kids when the HOV lane sticker runs out
> and buy a lithium battery Prius (hopefully plug-in!) to replace it.
> Since much of the grid energy derives from coal, hydro, and nuclear
> sources, plug-in is a great way to clip the petro umbilical and stop
> writing checks to people who hate us.
not to mention reduced greenhouse gases? :-)
main reason i'm asking about the lithium ions is that i had a job interview
a couple months ago with a company in S.C. who makes membranes for lithium
ion batts and that said they were going to be in priuses in 2010 - 2011 -
was curious if they were blowing smoke, which i believe they were......
bob
Posted by Bob & Holly Wilson on April 3, 2008, 1:16 am
> when will this technology be in the new ones?
There is no way to know.
> will you be able to use lithium ion batteries as replacements for the ni mh
> currently in them?
No. The battery chemistries are different as are their operational
characteristics. You really need to have an integrated battery
controller that knows job 1 is to protect the batteries.
Do the following experiment, replace some of your NiCD or NiMH battery
powered equipment with LiON and tell us how well it works out. You can
buy them at Radio Shack.
Use something that is easy to replace. For example, a flashlight.
Bob Wilson
Posted by Chas Gill on April 3, 2008, 10:28 pm
>> when will this technology be in the new ones?
> There is no way to know.
>> will you be able to use lithium ion batteries as replacements for the ni
>> mh
>> currently in them?
> No. The battery chemistries are different as are their operational
> characteristics. You really need to have an integrated battery
> controller that knows job 1 is to protect the batteries.
> Do the following experiment, replace some of your NiCD or NiMH battery
> powered equipment with LiON and tell us how well it works out. You can
> buy them at Radio Shack.
> Use something that is easy to replace. For example, a flashlight.
> Bob Wilson
So, give us a clue - what will happen?
By the by, I believe the Prius has a battery controller that does, indeed,
put the health of the battery first. No doubt, however, that it won't work
for LiON cells.
I also believe that plug-in to charge Prius after market 3rd party upgrades
are available (at a huge cost and doubling the current space taken by the
factory spec. battery) which give considerably greater range. OK if you
don't need the trunk space, I guess........
Chas
> will you be able to use lithium ion batteries as replacements for the ni
> mh currently in them?