snip
Todd Dore's 48-cell pack would require only 4 of these chips! i've requested samples from Maxim (twice) but have received nothing yet (others seeing same shortages/non-response).
i've since received the max11068 samples (twice, since i reordered thinking they lost the first order). However, i think reception of the samples now is because Maxim has just introduced their 2nd-gen IC (the max17830) that more or less obsoletes the max11068. The max17830 is listed as a future product (yet, i've requested samples already):
http://www.maxim-ic.com/datasheet/index.mvp/id/7114In the meantime, Linear has just introduced their 2nd-gen chip, the LTC6803. Here's the press release:
http://www.linearnews.com/press/LTC6803/LTC6803.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+LinearTechnology+%28Linear+Technology%29&utm_content=Google+ReaderWhat i take away from this is that the electronics manufacturers GET IT about electric vehicles and our needs for such IC's to enable our development! i'll try to sample the LTC6803 and see if/when i get it (probability looks poor since it's predecessor the LTC6802 was never really available for experimenter-types).
The 2nd-gen chips offer higher voltage (more cells handled per chip), more accurate readings (maxim 0.1%, linear 0.25%), faster measurements (100hz for whole pack), parallel and serially cascade-able processor interfaces (to support multiple and/or parallel battery packs), and one of the coolest things, support for external higher-power balancing MOSFETS (the internal balancing MOSFETS are fine for level-1/level-2 charging, but inadequate for rapid DC charging). You can almost read the future of EV technology by seeing what these chips can do (and visa versa)!
i forecast that EVentually each battery cell has it's own high-current controller (like a miniature version of our EV controllers) to control the power going in (regen/charging) and out (acceleration/balancing). We've come a long way folks... :-)
More l8tr...