Is it really true that before her, France can't win any battle against England?

Pitched battles were relatively rare in the Hundred Years War, since they were viewed as being too high risk to seek out. Generally they only occurred when one side was outmaneuvered and had no chance of escape (e.g. Poitiers, Agincourt). The vast majority of fighting in the war took place during sieges, of which the French won quite a few, especially across the period of the 1360s to 1380s when almost all of England's gains in northern and western France were reversed by the French. King Charles V of France (r. 1364-80) favoured a strategy of avoiding the English armies in the field, and instead dispersing his forces over as wide an area as possible so the English couldn't solidify their gains - since France had a vastly larger population, this was feasible for them and all but impossible for the English to successful counter. While there were no major pitched battles between English and French armies in the intervening period between Poitiers (1356) and Agincourt (1415), the French were pretty successful at offensive sieges and used their numerical superiority to their advantage, retaking many castles in the years following the Treaty of Bretigny (1360) and reducing English holdings to Calais and the land around Bordeaux (essentially where they'd been all the way back in 1337).

For all intents and purposes the war was practically over by the 1380s with the ascension of King Richard II (r. 1377-99), who had little interest in war with France and was content to just defend Calais and Bordeaux, and especially King Henry IV (r. 1399-1413) who was on friendly terms with the French government. During the reigns of these two kings it was pretty clear that France had all but won, since they'd retaken everything they'd lost except Calais. Only when the ambitious and glory-hungry Henry V (r. 1413-22) became king did the war promptly resume with his invasion of Normandy (which had been reconquered by the French decades earlier).

And did the war end after her time?

Yes, much later. Joan was captured in 1430 and executed the year after. The war wouldn't de facto end until 1453 with the decisive French victory at the Battle of Castillon, the last serious attempt in the 15th century by a large English army to seek victory. However, no official treaties were signed ending the war, hostilities just fizzled out. The English - led by King Henry VIII (r. 1509-47) would invade northern France twice in the early 16th century with the intention of conquering territory, but both campaigns ended in failure. I haven't come across any historians that consider these 16th century campaigns to be part of the Hundred Years War, however. Almost all of them consider the year of 1453 to be the final year of the war. As an interesting bit of historical trivia, English and later British kings would keep using the formal title of "King of France" all the way to 1801, when George III quietly dropped it when peace was signed with Napoleon.

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Sources:

The Hundred Years War: Volumes I-IV by Jonathan Sumption