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Build a high precision circuit for charging/discharging Li-ion batteries

€30-250 EUR

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Publicado há mais de 7 anos

€30-250 EUR

Pago na entrega
I'd like to build a high precision circuit for charging/discharging Li-ion batteries with the ability to monitor current, capacity, voltage, and temperature versus time. The circuit should have the following characteristics: 1) Ideally powered from the 5 V pin on a Raspberry Pi (this is somewhat negotiable) 2) Can charge a battery to 4.5 V and discharge to 2.5 V (discharge to 0 V is better) 3) Have constant current (CC) and constant voltage (CV) mode capabilities where the circuit switches from CC to CV at a programmable user defined voltage. For example, the circuit would do constant current charging to 4.2 V, then hold at 4.2 V for a period of time, then discharge to 3 V, and repeat. I suspect the circuit will look something like this : Figure 1 at [login to view URL], but it does not need to 4) Constant current is programmable (e.g. using a Raspberry Pi, python, i2c and a DAC). Ideally the DAC is an MCP4725 ([login to view URL]) 5) Constant voltage is programmable (e.g. using a Raspberry Pi, python, i2c and a DAC). Ideally the DAC is an MCP4725. 6) In constant current mode the current does not vary by more than 0.1% 7) Current range of -100 to +100 mA. Being able to both sink and source current is important (e.g. discharge/charge) 8) In constant voltage mode the voltage does not vary by more than 1 mV 9) Programmable voltage range of 2.5 to 4.5 V (ideally 0 - 4.5 V) 10) All components can be tested on a bread board (e.g. no surface mount components unless they can be found on an inexpensive breakout board like the MCP4725: [login to view URL]) 11) Voltage measurements (e.g. ADC) are made with an ADS1115 ([login to view URL]) 12) Current measurements are also made with an ADS1115 across a shunt resistor with minimal resistance drift and low temperature co-efficient. Must be able to read negative and positive currents (e.g. charge/discharge currents). Shunt resistor should be in series with the battery immediately in front of, or behind. 13) To accomplish above accuracy I assume a voltage regulator/shunt is required 14) Complete bill of materials 15) Circuit diagram and PCB design done in ExpressPCB software ([login to view URL]) including a Raspberry Pi header with male/female pins (e.g. so the board can be mounted directly to a Raspberry Pi and all pins are still accessible). PCB layout should include mounting holes so the board can be secured to the Pi using standoffs. Also PCB should not be larger than the Raspberry Pi 3 board in width or length 16) Description of how the circuit operates 17) Reasonable amount of technical support during building/testing Miles Stones: 1) Circuit Diagram (35%) 2) PCB Express design with BOM (35%) 3) Working circuit (bought, built and tested by me) (30%)
ID do Projeto: 12612817

Sobre o projeto

20 propostas
Projeto remoto
Ativo há 7 anos

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20 freelancers estão ofertando em média €735 EUR for esse trabalho
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hi, i am an electrical engineer. i have expertise in embedded system design and Matlab.i can help you with this project. Kindly reply back and let us discuss project further then i can prepare a detailed work proposal for the project. regards
€1.200 EUR em 15 dias
4,8 (76 avaliações)
7,7
7,7
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Hello. I'm an electrical engineer / PCB designer. You may check my qualificationin the profile. We can discuss any details in the chat (it will be a challenge to achieve desired tolerance). Will do my best. Viktor
€1.200 EUR em 25 dias
4,9 (208 avaliações)
7,5
7,5
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Hi sir, We have designed many projects in which we used battery management, we have read your project and ready to offer you our solutions at very low and affordable rates. Please discuss with us, we assure you the best we can. We assure you the quality of service through various checks that are employed to avoid any compromise on quality of work. Let me introduce my team to you and generally what services we offer to our clients. We are team of expert engineers and developers (8+ years of experiences) who are sound experienced in embedded systems (arduino + other microcontrollers), programming, circuit designs, electronics, product designs, pcb layouts, database management, MySQL etc. We offer you our services at very low rates. Please discuss with us in details. We will deliver design and code, if you want us to send you prototype, you have to pay additional charges of prototyping and courier such as dhl etc. We are very friendly in nature and help our clients during and after projects completion. We are flexible in communications and rates. Very much looking forward to hear from you on this in coming days. Regards, Ahmed Lead Technical Engineer Turktroniks
€200 EUR em 9 dias
4,8 (44 avaliações)
6,7
6,7
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Hi, I am a post graduate power electronics engineer and having very good experience in product design and development. I am excellent in embedded programming using pic, dspic controllers and MATLAB codding for Power projects, Boot loaders, EEprom. I designed sine wave inverters for standalone and grid tie Inverters. I designed projects like Off line UPS up to 3 KVA, synchronous rectifiers, Solar MPPT chargers, Battery chargers ,Grid tie inverters design with PLL and feedback control circuit emergency light of 66W and Online UPS control cards, Battery Charging power supplies, LED drivers for PWM controlling and dimming, SMPS, Power supplies. I have experience in schematics and PCB design experience in Altium and ORCAD. I am ready to work for you. Please contact for further discussion.
€777 EUR em 20 dias
4,9 (61 avaliações)
6,7
6,7
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Hello, Have a great day. we will ship you fully working hardware and we will take care of ROHS compliance. Please feel free to contact us. Best Regards, Shahbaz.
€2.000 EUR em 30 dias
4,6 (50 avaliações)
7,0
7,0
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Hello I have used these ADC and DAC many times for digitally controlled power supplies but not with RPi, probably you are using RPi for other purpose and this is a kind of add on. You will need a Adjustable Regulator, as output (unless you want it out of DAC only, using a buffer) Sinking and sourcing current sourcing is OK. Do you want me to code? Thanks
€377 EUR em 12 dias
5,0 (11 avaliações)
4,3
4,3
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Hello, I have several years design experience developing circuits and boards for various applications. These include spectrometer readout systems, analytical instruments, USB isolators, Microcontroller boards, Modular Conveyor systems, DC/DC converters, battery banks, etc. I typically use Eagle 6.5 for schematics and layout (I am familiar with others), LTSpice for simulation. I have also developed chemical processing and distribution equipment, medical devices, factory automation systems,and others. Best regards, Stuart Borden.
€1.000 EUR em 15 dias
5,0 (6 avaliações)
4,3
4,3
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Dear employer, I'm an electronics engineer with more than 4 years making product for customers around the world. I have experience with Raspberry Pi, MCUs, ADC/DAC and Power Supply design. I can also design the schematic and PCB by using the tool that you want. I designed some boards using ADS1115 and solar changer for Li-Po battery. Feel free to chat for further discussion!
€700 EUR em 10 dias
5,0 (8 avaliações)
3,9
3,9
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i am an Electronics Engineer with MS in Electrical Engineering. I have done many hardward and software projects related to this field. I have written 4 international research papers and one of them is related to power supplies. From this you can analyze my capabilities. looking forward to work with you and make a long lasting relation. my bid can b adjusted on demand. I will guarantee the perfectness of the task. Best Regards.
€188 EUR em 10 dias
4,9 (17 avaliações)
3,6
3,6
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A proposal has not yet been provided
€1.000 EUR em 45 dias
5,0 (1 avaliação)
1,8
1,8
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A proposal has not yet been provided
€222 EUR em 10 dias
0,0 (0 avaliações)
0,0
0,0
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FREELANCER RECOMMENDED ------------------------------------------------------ Can help... I am an Expert... Lets Start! Please start a Discussion with me and we can get started from there... Please check the past projects I have handled and check my reviews for what employers have to say about my work... Can start right now...
€1.000 EUR em 7 dias
0,0 (0 avaliações)
4,6
4,6
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A proposal has not yet been provided
€155 EUR em 3 dias
0,0 (0 avaliações)
0,0
0,0
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Hello sir, i understand your requirment sir. i am the perfect person for this job. i assure you that sir you will be happy after see my work. i will provide you best ever work which you want. i hope you will contact me . i am waiting for your response sir. have a good day thank you
€744 EUR em 8 dias
0,0 (0 avaliações)
0,0
0,0

Sobre o cliente

Bandeira do(a) CANADA
St. Croix, Canada
5,0
2
Método de pagamento verificado
Membro desde ago. 22, 2016

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