Good evening nileshhande.
I think you would come to something like this then .http://focus.ti.com.cn/cn/lit/an/slua097/slua097.pdf
There are dozens of chips to build smps's and lithium ion chargers .
But let me add a few points .
Building a switchmode powersupply is in itself very well possible when you have the acces to an ossciloscope etc.
The power doesnt have to be high for this half a Ampere would do so topswitch ,Fairchild fps anything will do .
(although i would prefer to build forward instead if flyback cause it saves the trouble of gapped cores)
About the charging part there it really doesnt matter which chipset you choose .
For me the criterium would be if its dil sockets .
It can be the TI from the datasheet or some other chip like it.http://focus.ti.com/lit/ds/symlink/bq2954.pdf
I know Microchip has them too like the 16HV785.
( and be carefull with mains power