Development of a connected Battery Management System

Cancelled Posted 7 years ago Paid on delivery
Cancelled Paid on delivery

For the next stage of the product, a passive and connected BMS is needed.

It has the task to be capable of balancing either 18650 Li-Ion Cells from Laptops OR Li-Ion batteries from various smartphone models. These batteries are usually 3+ years old and in different conditions regarding SoC. It is not known how long these individual cells will last, how many cycles they had or which conditions they had before. Apart from that, they also have different ages (which affects Li-Ion lifecycle as well). The BMS must be a connected product - meaning that it is able to send predefined data via a GSM module to the cloud (e.g. Google Sheets) in order to ensure efficient monitoring and replacement for end customers.

Key Technical Parameters:

- Needs to be finished within 90 Days (a very well functioning prototype, that can work without any maintenance in a remote area)

- Passive Balancing BMS with one or multiple coulomb counters that detect charging data of cells

- The BMS is going to be a 3-cell/ 12V system. Number of batteries in parallel is highly flexible and based on customer demand (can easily reach 100+ cells)

- The BMS must be able to handle different Voltage ranges (dependant on the configuration of Smartphone Batteries. Nominal Voltages that it should be able to handle: 11.1V 12V 12.6V 10.8V

- Must work with 18650s AND smartphone batteries

- Maximum continuous discharge current: 15A

- Maximum continuous current: 15A

- Cut-Off Voltage: 2.75V (18650) // Cut-Off Voltage for Smartphone batteries will vary and the BMS needs to be able to program individual voltages for batteries in parallel

- Charge Voltage: 4.2V (18650) // Charging Voltage for Smartphone batteries will vary and the BMS needs to be able to program individual voltages for batteries in parallel

- Operating Temperature Range: -10 - 60°

- BMS needs to have the ability to automatically detect if one or more cells have been taken out of the battery or added

- Integrated charging Circuit

- Integrated Temperature sensor for multiple (maybe all) cells

Voltage measurements for all cells

- Connection to a GSM Module and ability to sent Data in real time to a Cloud Spreadsheet (e.g. Google Sheets)

- Prediction system to understand in advance, which battery cells need to be replaced as they reached their end of life (in Form of a mathematical heuristic model, hardcoded into the BMS Software Stack)

- GPS positioning of the battery bank and ability to sent the Latitude and Longitude Data in real time to a Cloud Spreadsheet (e.g. Google Sheets)

- The BMS prototype will be build via Black Rabbit Developer Kit

Required skills:

- State of Charge circuit to sense the charge level of the battery and store the data in the register

- To design a circuit for Charge Current Limit, to cut-off the charging voltage once the desired level of SoC is reached

- To design a circuit for Discharge Current Limit, to cut-off the discharging voltage once the desired level of SoC is reached

- Overall communication with the central controller with either of the BUS topology

- Design of Protection circuit, to restrict overflow charge and over discharge of the battery up to the certain level.

- Design of Current protection circuit

- Design of Voltage protection circuit

- Integration of a temperature sensor measuring each cell’s temperature

- Passive Cell Balancing experience & knowledge about ICs

- Knowledge about Lithium-Ion batteries

- Software & Coding experience (incl. Developing/implementing the SoC algorithms)

- Ability to make a full-stack PCB design (surface mount devices (SMD) components). - MUX Circuits could be a relevant and useful

Coding Electronics

Project ID: #13377668

About the project

5 proposals Remote project Active 6 years ago

5 freelancers are bidding on average ₹35889 for this job

ahmad5857

Hi Sir, I have designed many BMS based on LTC6802, LTC6804 etc for management of LiPo battery cells. I have designed very large BMS systems. we incorporated undervoltage and over voltage protections, temperature pr More

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jitendrabaraiya

A proposal has not yet been provided

₹50000 INR in 30 days
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aruntank2000

I m best in designing

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