To begin with, using some other charger than the one provided by the manufacturer will not be a good idea. The battery on your smartphone is designed for a particular charge and voltage. Using a high capacity charger may result in faster charging initially, it can have detrimental effects on the battery lifetime. You could even get your battery burst, or face fire issues.
Having said that, here are a few chargers that may be helpful.
1. USB Mobile Phone Wall Charger
It is available on Maxbhi.com. The high capacity charger can be bought at Rs. 295. It assures quicker charging. It can be used as wall charger or for charging/connecting your phone to PC/Laptop.
2. Micro USB Black Charger
The charger is priced at Rs. 249. You may buy it from rediff.com. The charger can be used to connect your device to computers as well. Please note you need to pay Rs. 49 towards shipping.
Even with the availability of these ( and many other) chargers both online and offline, I would still insist on going for a charger from manufacturer itself. Check if Xiaomi has any fast charger for your model. High output chargers can charge your phone faster, at the same time they will reduce the lifetime of your battery.
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