Fabeyes, I think LiPoly might eventually become the dominant battery in the electronics area; but I have no reliable opinion how long this would take. In terms of numbers of batteries, the electronics market is huge - far larger than the EV market could be. I have seen the numbers but do not remember them. The SI VLNC Board will no doubt have posts giving this information. In terms of total energy capacity, perhaps the EV market will eventually be larger.
Here is a commentary on the article I posted earlier. Interesting observations about the safety issues of Lithium Batteries. From the SI VLNC Board:
To: I. N. Vester (8058 )
From: Dennis V.
Saturday, Feb 6 1999 7:00PM ET
Reply # of 8066
I.N.,interesting article, but actually omits certain safety concerns in keeping with the
source (company PR). Differences in electrode materials and electrolyte have real
effects. However, even where the chemistries are similar to poly, no liquid electrolyte,
cannister battery has passed the nail gun test. Often, when pierced by a high speed
projectile they explode into flame. Plastic batteries usually endure this test without
catastrophic results. There are safety differences between cobalt and manganese(spinel)
batteries. VERY careful regulation during charging is mandatory for cobalt
batteries(liquid or plastic). In keeping with this, the article addressed the need for
regulating circuits, thermal links and current limiters to protect against temp rise, short
circuits and overcharge. Overcharging the cobalt battery can cause metallic lithium to be
electroplated onto the cathode, causing a fire. The manganese battery is not susceptible
to the latter problem, but does, naturally, require charge control. Other safeguards,
similar to those listed above may be elected by the manufacturer. The referenced article
omitted the safety concerns attendant to the lithium metal electrodes used in the Moltech
battery. Charge, discharge cycles cause lithium to "migrate" and form
dendrites(icesickles) which can pierce the separators causing internal short circuits and
fire. In spite of efforts to suppress dendrite formation, this type of battery can only be
safely cycled a couple hundred times vice 500 times for the manganese battery and
cobalt battery.
The above is not complete or comprehensive, merely illustrative. People who know a lot
about this stuff would likely point out that the particular safety concerns are manageable
during manufacture. However, as Lev apparently discussed, there are diminishing
returns in safety, cost, size, or level of confidence for larger cobalt poly batteries, in
particular.
Last thought concerning the remark that laptops might not use li poly batteries. Other
than safety concerns that Valence already has control of, there is the problem of cooling
a laptop computer in which the li poly battery's flat shape may block air circulation to
the electronics. Some design compromises might be a point of discussion depending on
the types and models.
D.V.
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