To: Chisy who wrote (13774 ) 8/16/1999 7:38:00 PM From: Rich Wolf Read Replies (1) | Respond to of 27311
Chisy, don't know who's in the Nokia now. But I know one thing: No advertised li-ion battery spec is equal to that of the cellphone cells that Valence sent out from the *commercial production lines* at the NI factory back in July. None. Any phone's performance will depend on how big a cell they put in the phone, but you can rest assured that for a given size space for a cell, the Valence cells have the highest energy density: 142 wh/kg, versus a *max* of 136 wh/kg for the best li-ion prismatic cell, which cannot be made thinner than 8.5mm for this spec (only one Japanese manufacturer has attained this, GS, using aluminum cans; they're a small player, too). Conversely, the Valence cell could be made any thickness with about the same energy density spec. Thinner li-ion cells have specs below 120 wh/kg, and many are down near 100 wh/kg (e.g., the Polystor cells). Someone who wants to make a thinner and lighter phone would want to use the Valence cell, no doubt about it. Certainly they'll have issues about second sourcing: there would be no alternative suppliers for the thinner cells until the other li-poly manufacturers get their acts together, but by all accounts their cell specs don't match Valence's either. (That's part of the reason you haven't seen much from TDI or SAFT, after all the noise they made.) It'll be an interesting fall, seeing what products the Valence cells end up in. Caveat: specs are always a moving target. But remember Valence has already surpassed their own specs above by a wide margin, too (using the lithium-phosphate cathode materials to achieve around 170 wh/kg, from estimates; this also for any thinness of cells).