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New Project - Battery Electronics

We have a new electrical design project that interfaces to a new battery technology. The electronics need to monitor cells and generate several DC voltages.  Some first pass (and adjustable) specs provided to us are below.  It may be helpful to have a discussion on ADI technologies that may fit for this project.

Data logging:

What to log:

  1. Each cell voltage
  2. Current efficiency relative MEP
  3. Remaining primary battery capacity
  4. Total power output
  5. Ambient temperature
  6. Ambient pressure
  7. Ambient water conductivity
  8. Voltage and current drawn by each power rail
  9. Charging / discharging rate of peak power battery
  10. State of peak power battery charge

When to log:

            Log each channel (Ncells + 2*Nrails + 7) once every 5 seconds and at events like large changes in power draw. Write to CSV file in flash memory (2GB should last over a year)

How to retrieve:

            A USB header should be accessible, and we’ll provide a cable for access as a mass storage device.  Alternatively, use an SD card or thumb drive if it can be appropriately waterproofed and still be removed after use.

User-Available Power Outputs:

            Up to 8 power channels based on cost and efficiency, to be informed by Boston Engineering.  Candidate rails (high priority voltages in bold, low priority in italics): 1.8V, 3.3V, 5V, 9V, 12V, 18V, 24V, 30V.

Visual Data Indicators:

User-Available Analog Data:

User-Available I2C / Serial Data:

            All logged values.

Peak Power Battery (PPB) Management:

            Peak power battery is likely a LiPo battery of around 10Wh of capacity

            Peak sustained total power output across all power rails of about 150W

The PPB should be charged thoughtfully, taking care to run the primary battery (PB) at MEP whenever possible, balanced against the risk of depleting the PPB in sustained high-power draw scenarios.  Finalizing this protocol may need to be informed by the efficiency of charging and then discharging the peak battery.

            Suggested charge protocol:

  1. 1.      If PPB charge is >75% and user power draw is <MEP, run PB at MEP and divert the additional power to charging PPB.
  2. 2.      If PPB charge is >75% and user power draw is over MEP, don’t charge PPB.
  3. 3.      If PPB charge is <75%, run PB at MPP regardless of user power draw and divert additional power to charging PPB.