16kW-hr battery packs made from lithium ion cells are powering electric vehicles and storing grid energy. Measurement ICs like the LTC6804 are used to extend the life and ensure the safety of the pack. The accuracy of the measurement IC can influence the cost of the system. The LTC6804 can measure cell voltages with less than 1.2mV of total error. Groups of LTC6804 ICs can measure 100’s of cells quickly and accurately in noisy conditions. Accurate measurements mean fewer battery cells are needed to meet an energy storage requirement. Several integrated circuits on the market measure battery cells. The LTC6804’s unique zener voltage reference makes it performance superior. The LTC6804 maintains its accuracy after severe thermal stress, humidity and for years in service. The new “isoSPI” 2-wire isolated data interface further reduces the battery pack component count while increasing the immunity to electromagnetic interference. Precision data acquisition, robust performance and a simple schematic make the LTC6804 a new standard for battery cell monitoring.