How to charge the E-card battery?

Our engineers have succeeded in the development of an ultrathin, flexible, rechargeable Polymer lithium battery. The thickness of such Ultrathin Polymer-Li Battery (UPLB) is only 0.40mm. will used for Smart banking cards and credit cards.
So I do not know how to charge the battery in the card?

That's pretty neat.

Are you asking how to manage the charge and voltage on the battery, or how to actually get power into a card without a big connector?

no we can charge because power we can send through frquency such as we get dat through card and we give data to card like we can do that same work.
as i think

Lithium Polimer batteries are generally charged by using Constant Current-Constant Voltage(CCCV) method.......it is very senstive to over charging and disharging......say if it is overcharged by 15% extra of its capacity it can result in damage(or some catastrophic effect) due to gasing......

In your case eventhough battery capacity is low only ocasionally you are going to use your card on which you are going to mount the battery......charging depends on your source supply(or the duty cycle of the signals through which you are planning to charge the battery),form factor(ofcourse in your case).....i feel feel you can use linear li=polymer batetry charger....but a really not sure how small that would be comparable with your batetry or card reader....i have used some bigger ones only since my current rating where in amps range.....

You can find a lot of general journals and products which can be used to charge a Li-polymer battery......

hope this helps and not really sure if i understood your requirement corectly....

B.T.W. its a coool product......