Need Help with a Deep-Discharge Circuit !

Thread Starter

offtherails2010

Joined Dec 31, 2011
3
Hello & Good day to everyone!

I have put together a 'power-pack' from four 3.6v 18650 batteries having 14.4v in total... (in series at the moment, can change if needed...)

I'm pretty new to electronics and have a few basic skills with soldering etc, what i am trying to make is a Circuit that stops my power-pack from deep discharge but to make it as simple as possible...

Found this circuit below:

http://dmohankumar.wordpress.com/2010/05/15/battery-over-discharge-indicator/

(credit to D.Mohankumar!)

But i need to augment the circuit to allow for 14.4v battery pack, How do i do this & where do i start ? (what equations do i need here :confused:) I am learning as i go but the only way i learn is to kinda immerse myself in the deep-end!

Eventually i need the power-pack to emit 8v and no more than 200mA, would i be able to incorporate both circuits in one ? (Deep-Discharge Preventative circuit + voltage drop circuit) ???

I have the following:

- medium selection of voltage regulator semiconductors
- selection of resistors
- selection of capacitors (ceramic & electrolytic only)
- selection of transistors (NPN & PNP)
- Four 18650 type 3.6v batteries
- Breadboard
- A Fast-Study-Mind ! (lol)

Please could anyone help me get closer to finishing off this project ?

A Great Many many thanks in advance for any/all help received !
 

k7elp60

Joined Nov 4, 2008
562
Hello & Good day to everyone!

I have put together a 'power-pack' from four 3.6v 18650 batteries having 14.4v in total... (in series at the moment, can change if needed...)

I'm pretty new to electronics and have a few basic skills with soldering etc, what i am trying to make is a Circuit that stops my power-pack from deep discharge but to make it as simple as possible...

Found this circuit below:

http://dmohankumar.wordpress.com/2010/05/15/battery-over-discharge-indicator/

(credit to D.Mohankumar!)

But i need to augment the circuit to allow for 14.4v battery pack, How do i do this & where do i start ? (what equations do i need here :confused:) I am learning as i go but the only way i learn is to kinda immerse myself in the deep-end!

Eventually i need the power-pack to emit 8v and no more than 200mA, would i be able to incorporate both circuits in one ? (Deep-Discharge Preventative circuit + voltage drop circuit) ???

I have the following:

- medium selection of voltage regulator semiconductors
- selection of resistors
- selection of capacitors (ceramic & electrolytic only)
- selection of transistors (NPN & PNP)
- Four 18650 type 3.6v batteries
- Breadboard
- A Fast-Study-Mind ! (lol)

Please could anyone help me get closer to finishing off this project ?

A Great Many many thanks in advance for any/all help received !
I'm not sure that I fully understand what you wish to do. If the battery has a 14.4 voltage at full charge, do you wish to stop the discharge when the voltage drops to 8V? Do you also wish to limit the discharge current to 200mA?
 

Smoke_Maker

Joined Sep 24, 2007
126
Hello & Good day to everyone!

I have put together a 'power-pack' from four 3.6v 18650 batteries having 14.4v in total... (in series at the moment, can change if needed...)

I'm pretty new to electronics and have a few basic skills with soldering etc, what i am trying to make is a Circuit that stops my power-pack from deep discharge but to make it as simple as possible...

You will need all of that and more, to protect the battery form the user isn't easy. Start here
http://www.mpoweruk.com/protection.htm
http://www.mpoweruk.com/bms.htm

it's doable and your doing it right "both feet"

Don't get discouraged this will be a long and fun adventure, we are here for you.
 

Smoke_Maker

Joined Sep 24, 2007
126
Hello & Good day to everyone!

Found this circuit below:

http://dmohankumar.wordpress.com/2010/05/15/battery-over-discharge-indicator/

(credit to D.Mohankumar!)

But i need to augment the circuit to allow for 14.4v battery pack, How do i do this & where do i start ? (what equations do i need here :confused:) I am learning as i go but the only way i learn is to kinda immerse myself in the deep-end!

A good place to start is to build that circuit and rework it for your voltage.

here is another circuit
http://www.metricmind.com/ac_honda/images/clamper.jpg
http://www.metricmind.com/ac_honda/bms.htm

Look this over
http://agnimotors.com/home/index.php?option=com_content&task=view&id=27&Itemid=39
 
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