Solar Based Battery Charger.....

The primary thing would be how efficiently we use the solar energy and store it.

Understanding of MPPT(Maximum Power Point Tracking) can help in utilizing solar energy efficiently.

I am basically trying to rig up a circuit around LTC1734 (datasheet). This will be supplied with 6v 300mA from the solar panel and this 2 watt panel will pump about 1.8 amp-hours into a battery.

And this circuitry will not be doing the MPPT function but apart from this what is to be taken care???

Please feel free to support me with this design.

Hi Mujahid,

What is the end application of this Battery Charger and why did you choose Li-ion battery ?

Thank you,

Chethanrs

Hi Chetan,

As described, the device can be used to charge Li-ion battery which are most commonly used in Mobiles and PDA's and other most portable devices (that is why I have chosen Li-ion battery). The end application is when one finds he has no access to grid power and the solar is available example when he is on trekking or outskirts.

HI,

I have a doubt regarding Battery connectors in mobile, I can see 3 pins available on top of mobile battery, what does this 3 pins signify?

Thank you,

Chethanrs

Dear Mujahid,

Making use of MPPT is pretty much essential for loading an solar panel. The output power fluctuates over light intensity and temperature. If you look at the output power curves you will understand that not regulated on the maximum power will make your design far less effective. I have seen an application note on the Microchip website suggesting a microcontroller (PICmicro) to have a boost (DC/DC-converter) with MPPT on the solar panel. It is hard to circumvent microcontrollers in this kind of complex applications.

Best regards,

Enrico Migchels

Power conversion design engineer

Best - The Netherlands

www.heliox.nl

I agree with you but i just have a doubt on the ciruit below using LTC1734.This is a direct solution from LTC. Inother words could you let me know the which could be the best MMPT IC to be used along witht he LTC1734 here???

Hi Mujahid,

The LTC is 'just' a battery charger which regulates the current trough and the voltage of the battery. Your solar charger must have the same charge characteristic as the LTC1730 but additional have a converter on the input stage which regulates the energy coming from the PV cells to a fixed DC voltage with maximum power tracking incoperated. Look at AN1211 'maximum power solar converter' on www.microchip.com to see what i mean. I would say that if you use a microcontroller for this function it might as well regulate the current through the battery and measure the output voltage.

Best regards,

Enrico Migchels

Power conversion design engineer

Heliox B.V.

Best - The Netherlands

www.heliox.nl

Hi Enrico,

thank you for you valuable feedback and will just check with MPPT and get back. Please let me any redy designs that you know of on for solar panel and will be very helpful.

Hi Arun,

Any ideas on MPPT ic in specific to help with me with my design?