Arduino True Battery Capacity Tester (Li-Ion/NiMH/NiCD/Pb)

Step 8 Discharge Circuit

very simple with the 2 A/D connected on the two sides of the resistor /
Vr=Vbat-Vfet.

Comments

[paulryanmini]

hi all
fixed the code after a long night. i can get the setup to start up and the lcd turns on. it will then pick up what type of battery is connected and will measure the voltage and current of the battery, but the led wont illuminate which leads me to believe the mosfet is not switching on. im using a irf540a with a rds on of .052 ohms. any ideas?

Ive been using a 1.3v 1200mah AA rechargeable battery nimh.

any ideas?
thanks

[monbeamdistilleries]

Im having the same problem with the same part. Also trying to reduce the required display size from a 24x2 to a 16x2. Great circuit as I have tons of recycled/scavanged Li-ion cells to test before I use them making a new E-Bike battery pack.

[paulryanmini]

hi
i copied the code above directly into ardunio 0022 program. i have the duemilanove clone.

it comes up with the following errors:

dunkbat.cpp:3:10: error: #include expects "FILENAME" or
dunkbat:3: error: 'LiquidCrystal' does not name a type
dunkbat.cpp: In function 'void CL2()':
dunkbat:23: error: 'lcd' was not declared in this scope
dunkbat.cpp: In function 'void setup()':
dunkbat:31: error: 'lcd' was not declared in this scope
dunkbat.cpp: In function 'void loop()':
dunkbat:76: error: 'lcd' was not declared in this scope
dunkbat:99: error: 'lcd' was not declared in this scope


any ideas im a complete noob
thanks
paul

[abosebkk]

Dear paul

This is because the include file is not mentioned at the start. if you do: Sketch> Import Library>liquidcrystal , it will add the necessary header file to the sketch and compile correctly.

[slvr00gt]

Here is more detailed diagram of the same thing

[m_boby_k]

Hi slvr00gt, I' have seen your diagram but that's something I don't understand.
The FET voltage terminal is seems don't have connection to the drain circuit, how it's can give analog input (FET voltage) to arduino?

[slvr00gt]

Adding better quality diagram

[paulryanmini]

hi
its a fantastic circuit and ive started to build it. have you by any chance got a higher resolution of the diagram above i cant zoom in enough? thanks

[moris_zen]

I see some one made a diagram - great work

[slvr00gt]

Just added powerpoint file above.... My diagram jpeg was originally high quality, but this forum compressed it into nothing. So I added original ppt file

[blast09]

Sorry but I miss something...It seems to me there's a typo in PPT diagram.
Pin "fetVoltage[plus]" on discharge circuit is left floating around. Could you confirm this? Thanks for great work anyway.

[paulryanmini]

thanks very much. im building it as part of a assignment for power electronics.

i will then alter it to work with 36v 14ah lithium polymer batteries somehow :-) if you have any ideas that would be great