[DirtyDan]

"Deep cycle" batteries are made to discharge all or most of their juice and then recharge. Automotive batteries do not handle frequent near full discharges very well and this kind of usage shortens their life. In other countries people run two batteries, one automotive, one "deep cycle". Both get recharged from the alternator. However, a device known as an "isolator" is used to keep the two batteries separate as far as discharge. Thus the "deep cycle" battery powers the winch only while the auromotive battery is "isolated" from doing that. Also, most off-roaders abroad upgrade their alternators. 200 amp alternators are common abroad and are available in India, though I cannot vouch for their quality one way or the other.