Oh dear, I'm feeding the U.S. stereotype
Yes, I meant 100,000 kg, my bad.
Actually, the stockpile is always maintained, and half of them (2,200 warheads) are always ready. The other half are decaying away.
And again, no. No one realistically plans to "win" a nuclear war, unless it's against Iran or North Korea, at least while they're still developing their nukes. A nuclear exchange between two or more powers (e.g. between the U.S. and China), is only going to result in the death of millions, a crashed world economy, and lots of things going wrong.
And before I come off as too "pro-American", I'll just post a common statement used by people who are arguing the position of the U.S. in a US-PRC nuclear exchange "America would simply nuke the 3 Gorges and kill millions off the bat with the subsequent flooding".
Like I've said, even with China's small stock pile of some 50 to 60 truly ICBMs, they can deter America. Against Russia, China has it better as Russia is obviously closer, and can again, kill plenty of Russians. Russia or America v. China would result in similar fates with China, millions dead, millions dying. Nuclear war is totally not desirable, and neither is war in general, for that matter.
It isn't a "what's behind the curtain"-comparison contest, man, that's what I've been trying to tell you guys. The PRC can do fine with what they have already, in fact, I admire the fact that they aren't overdoing it like the US or the USSR and have just enough nukes stockpiled for the purpose of MAD at hand.