Cell balancing pcb’s are connected in parallel to the arduino BMS controller shield (comming soon, check out my Danish version of this site to follow the developing process, first 09beta version running now)

Functions in RC1 cell balancing PCB:

1. Detects Vlow (ca. 2,85 volt) and opto coupler patch info to the arduino based BMS controller
2. Detects Vhighhigh (4,2 volt) and opto coupler patch info to the arduino BMS controller
3. Balancing the cell at Vhigh with a load resistor, switched on with a Darlington transistor

This cell module can be used for electric vehicles with LiFePo4 batteris, just by changing some configuration in the arduino sketch, and a few components on the arduino BMS controller shield.

My inspiration for this project came from the raising amount of standard 18650 LiIon cells, i salvage from defect labtop batteries, and other LiIon driven electronic.

I simply hate to trough out things that works. Also i have a electic bicycle, cleaning robots and dream about making a eletric outboud boat motor, using salvaged cells, so i decided to make my own BMS, and use other components i had on the shelf doing nothing.

I had some transistors, power resistors, optocouplers, resistors and more, so thats why this first version is with analog leaded components.

This cell module can be modified to fit the new LTO battetry cell.

the cell module can NOT by it self disable the charger or turn of the load at Vlow. The cell module are not for standalone, they work together with the arduino BMS controller shield.

The picture above show the cell module with the 18650 LiIon cell from a dead labtop.

Often more cells in the labtop battery are in fully working condition, or the original cell pcb is defect. It is possible to get hånds of a lot of free LiIon cells for fully working DIY battery packs.

schematic for BMS cell pcb version RC1:

component placement Version RC1 of BMS cell pcb

Printlayout RC1 BMS cell pcb:

Bms Diy Arduino 08b

The ctek xs 3600 have 4 charge modes:

• Desulphation: pulses with high volt/amp is made
• Bulk: after 80% charge, the charger deliver a constant current until battery i fully charged
• Absorpsion: charge up to 100%, current will fall but the voltage will be constant
• Puls: this is a puls charge mode, it maintenace the battery, a keep it in goog condition. This mode charge between 95% and 100%. This is the mode used when charger is connected in months.

The ctek xs 3600 just have one issue, i don’t start up in the charge mode you selected, next time it is turned on.

To overcome this issue, i use a AtTiny85

AtTiny 85 pinout:

ATtiny Pin 1: RSEST
ATtiny Pin 2:
ATtiny Pin 3:
ATtiny Pin 4: GND
ATtiny Pin 5: Connected to ctek mode selector trough the 4066 analog switch
ATtiny Pin 6:
ATtiny Pin 7:
ATtiny Pin 8: 5 V

Ctek xs 3600 230 volt/110 volt AC input is connected to the Electric vehicle’s AC charger connector

This picture show a salvaged Pentium 4 cooling plate with fan mounted on top of it.

The complete MPPT solar charger is mounted to the cooling plate, using a aluminium U profile, where the MOSFETs and voltage regulator are placed.

The picture above shows the aluminium U profile, as You can se it is a few millimeters to wide..

To complete the mppt solar charger project, i still need to do some work with a plastic cabinet, and also i will make some kind of temperature controlled PWM speed adjustment for the fan.

Update 20-12-2014: this arduino mppt charger shield is tested and works withTim Nolans version of the arduino sketch. The placement of the mosfet’s on th

e circuit board was designed to fit to a Aluminium U profile.

Just make sure you don’t try to cool down the power from a 9 map solar panel, with this small aluminium Profile.

To do that, you need a bigger cooling plate. You can find a link in the article below for an example of how to use a salvaged pentium 4 cooling plate.

This project is inspired but the original Peak Power Tracker Battery Charger Project made by Tim Nolan. Unfortunally he’s website is down, so i will try to recover the specs and bilding material from his page.

The mppt solar charger with arduino is designed so a 12V (20 volt peak) solar panel  can do the charging of a 12V lead acid battery.

Tim Nolan used a Arduino Duemilanove development board, in this project i have used both Duemilanove and Uno (r3) as the basic platform.

Tim Nolan used a Arduino Protoshield Kit for he’s development, i did that in my first version, but i became more and more happy for this project, and desided to make my own pcb layout based on Tim Nolan’s original project.

The project original consist of a number of files, most still have fully working link

• PPT Charger schematic (EagleCAD), this link still works: ArduinoSolar.pdf
• PPT Charger Hardware Description: link to ArduinoSolarHardware.txt broken, but this stll works:  ArduinoSolarHardware.rtf
• PPT Charger Parts List still works : ArduinoSolarPartsList.txt
• PPT Charger Software (the original Arduino Sketch by Tim Nolan) is still online: ppt.pde
• PPT Charger Photos links are still working : Duemilanove and Protoshield, Prototshield back, Protoshield front

He made a article on http://www.homepower.com on how Peak Power Tracking works. The original article is still online: Peak Power Tracking article.pdf

More cooling options for te arduino mppt solar charger

Open source pcb made for Tim nolan’s mppt solar charger

This is a version rc1 of the pcb, and i will try using irl540 MOSFET instead of irfz44

Download eagle pcb and schematic source files:

Arduino MPPT shield schematic and pcb eagle files for rc1

Free thanks

The next experiment will be a slightly larger model of aluminum and mounted on the shaft / bearing from a scrapped ceiling fans. There must then find some neodymium magnets and wound some coils which must then be made ​​into a simple administrator.

A model of my small offgrid DIY VAWT wind turbine of cardboard and debris from two cdrom boxes.

The video above demonstrates that VAWT wind turbine rotor blades operate with air from a fan heater.

It has been tested in steady wind outdoors too, and it works.

Inspiration to experiment with VAWT wind turbine found here 

A scrapped ceiling fan contains bearings, shaft and casing for a generator. Counting on it can be made of some neodymium magnets and some self-wound coils.

Alternatively, a place Smooth-running motor is used as a bearing for a mini VAWT wind turbine.

It could make a lot of small VAWT turbines which are connected to a local smart grid that distributes power around your house with a DOS power rail. It would be a good addition to photovoltaics in the winter. The question is whether municipal, laws and regulations may prevent one set eg 10 mini VAWT wind turbines?

Links and ressourcess to VAWT small wind turbine

VAWT windmill 12V 50W Telescopic Vertical Axis Wind Turbine

Helix Wind design airfoils for VAWT windmill

strator design tobrushless permanent magnet generator

Video show the Helix Wind’s airfoils

 Links and ressourcer to more VAWT diy

 Strator, neudym magnets and other parts for VAWT windmill

This Arduino suntracker /solar tracker called: ‘Sun-Trackuino-Delsol’.

I use a Arduino with nuelectronics ethershield which is used a few times in the past as solar data logger and stokerlogger / controller with Arduino is a WebClient (Remember use ARDUINO IDE 0018 to ethershield from nuelectronics! ).

Unfortunately this shield is discontinued but you can use any other arduino ethernet shield but you must change the code.

I also have a version of the suntracker sketch without webserver

The picture here shows fumble shield PCB and Arduino can be glimpsed beneath.

Top t.v. sits a polulo acs714 flow sensor. Middle T. H. seen optokoplerne and motor control chip. In the right version replaced the chip by a mosfet H-bridge.

Forrest t.v. seen a 5 volt regulator with USB plug for charging the smartphone with the three small solar cells.

About code and hardware for suntracker beta

It is not expected to Arduino sketch can be downloaded below, is used for purposes other than this model which simulated sensors and actuator are made with a small gear motor and made of Lego technics. Hardware a been struggling the same on a fumble print. Perhaps, make a arduino / nabduino solar tracker shield at a time.

The video below shows what beta sketch can

For suntracker not continually face and running with actuator, has introduced a delay of X minutes between each time it is allowed to move the actuator to either east or west. For this there is used

dateTime library for arduino.

Ind til videre kører trackeren, der er et øst og vest endestop, og to aktive LDR der søger efter solens retning.

Actuator kan stoppes med en knap, og der kan via url sendes manuelle kommandoer om at gå mod øst eller vest .

Dette er en lille beta arduino sketch (til IDE0018)

Version 31-12-2012

Read techmind.dk GENERAL Disclaimer before you continue.

This version 1.1 if for single coil trafo’s also i made a prototype v.1.0 printed circuit board for trafo’s with center input.

Schematics for the arduino inverter

The component placement of the Printed Circuit Board

The arduino inverter PCB  Toplayer

PCB from the solder side

The eagle PCB file for inverter with arduino can be downloaded here

The original Arduino Sketch for the inverter. Thanks to bristolwatch  for this great project. Techmind version will be published latter.