The writer JG Ballard, who died in 2009, is a tantalising subject for a biographer. His extraordinary childhood in prewar Shanghai, his family’s subsequent internment in a Japanese prisoner-of-war camp, and the death of his wife, Mary, at the age of 34, were formative events in the creation of his unique vision. The vivid and sometimes shocking images he witnessed in his early life would resurface repeatedly in his fiction.

Yet he always resisted approaches from those keen to tell his story, and at the end of his life produced a curiously flat memoir, Miracles of Life. The author of this new biography, Christopher Priest, apparently admired that work, while recognising that it represented “a carefully curated account … of a messier reality”. As he points out, it revealed nothing that was not already known. An unauthorised biography by John Baxter appeared two years after Ballard’s death, which, though it has been criticised by Ballard’s family for inaccuracies, remains a useful introduction to the life and work of one of the most interesting writers of the postwar period.

In The Illuminated Man, Priest sets out to consolidate Ballard’s place in the literary pantheon – a difficult task, not least because Ballard chose to work in science fiction, a genre largely underrated in literary circles for most of his career. Even among science fiction writers, Ballard was an outlier. Rather than setting his stories in outer space, like the hard SF of the time, he explored what he called “inner space”, particularly the subconscious mind. It is no coincidence that his first choice of career was as a psychoanalyst. “Ballard’s talent is one of the most mysterious and distempered in modern English fiction – and it is by far the hardest to classify,” wrote Martin Amis, reviewing Ballard’s novel Hello America in 1981. “It is futile to have expectations of Ballard: he will inevitably subvert them. All we know for certain is that the novels he will write could not be written, could not even be guessed at, by anyone else.”

As Amis suggests, Ballard is a writer unlike any other, with his own distinct, strange and instantly recognisable voice. His characters are nondescript, referred to only by their surnames, and resigned to their fate. Most are obsessives of one kind or another. They are drawn to extreme environments, jungles and swamps, deserted cities or nuclear bomb sites. Certain images – drained swimming pools, abandoned shopping malls, empty apartment blocks – recur in story after story. As the writer and psychogeographer Iain Sinclair has observed, every book of his “is a repetition, an extension of the same riff”. The word “Ballardian” has entered the language. The untimely death of the young and beautiful Diana, Princess of Wales in a car crash was a Ballardian moment, as Salman Rushdie was one of several to recognise. The riot at the opening of a new Ikea store in Tottenham in 2005 was another. To his fans, Ballard has acquired the status of a prophet, a writer who depicts a world without meaning, a post-truth planet of environmental collapse, pointless violence and primitive regression.

Ballard seemed on the verge of entering the mainstream when his semi-autobiographical novel Empire of the Sun was shortlisted for the 1984 Booker prize. By its nature it marked a departure from his science fiction, though studded with some familiar Ballardian images, as Priest rightly notes. In the run-up to the Booker prize ceremony it was the hot favourite, but the judges chose instead to award the prize to Anita Brookner’s Hotel du Lac, a wistful and witty but nonetheless conventional novel.

Perhaps it was just as well that Ballard did not win. His talent was too anarchic and too unsettling for general acceptance. His 1970 novel The Atrocity Exhibition eschewed narrative cohesion to the extent of being incomprehensible to many. When 1974’s Crash, which explored the intersection of sex and violence in a particularly disturbing way, was submitted to Jonathan Cape, one of the publisher’s senior readers (so it was said) wrote in her report on the typescript, “This man is beyond psychiatric help. Do not publish.” Ballard himself claimed to be delighted by this criticism, which he considered a mark of artistic success. Though the Guardian reviewer of Crash lauded Ballard as “one of the few genuine surrealists this country has produced, the possessor of a terrifying and exhilarating imagination”, the New York Times reviewer characterised it as “hands-down, the most repulsive book I’ve yet to come across”. When Crash was filmed by the director David Cronenberg, the critic Alexander Walker condemned it as “a movie beyond the bounds of depravity”.

It was ironic that the author of such unsettling work was a quiet and serious family man, who lived most of his adult life in a modest suburban house in Shepperton. Though fascinated by technology, Ballard wrote his novels in longhand and typed them up himself. He did not own a computer and never had an email address. Ballard was uninterested in material possessions. His editor Malcom Edwards recalled how Ballard, on receiving the first payment for the film rights for Empire of the Sun, decided to splash out by visiting his local supermarket. After wandering the aisles for some time, he returned home with a tin of salmon.

As a writer of speculative fiction and a perceptive critic, Priest was well equipped to assess Ballard’s oeuvre. He advances some interesting ideas: for example, he maintains that “Ballard made a mistake when he wrote Empire of the Sun, that the work that came after was less intense, less radical, that in revealing the source of his inspiration he had drained himself dry.” His is a reliable and authoritative guide to Ballard’s work, in so far as it goes. But six months after starting the biography Priest was diagnosed with terminal cancer.

He hoped to live long enough to finish it, though as it turned out he was only able to write 65,000 words – perhaps half his intended total. The book has been completed by his partner, Nina Allan, also a novelist, who became his wife just before he died. Her contribution to Ballard’s biography consists largely of interviews, which she reproduces as gospel, though she quotes Ballard himself as saying that “the recollections of friends and acquaintances should be discounted”. There are gaps: the book mentions Ballard’s short story The Secret Autobiography of JGB****** only in passing, and omits altogether the provocatively entitled Why I Want to Fuck Ronald Reagan.

Woven into Allan’s narrative is an account of Priest’s final illness. Her description of his final days is almost unbearably poignant – though of course this has nothing to do with Ballard. It would be insensitive to criticise Allan when her grief stands out so starkly on the page. One might argue that such an oblique, multilayered approach could be appropriate for the life of an elusive subject like Ballard – though it was not the one Priest had planned to take. And it creates problems for the reader, not least in knowing who has written what. This is a brave and moving book, worth reading; but those seeking a conventional biography of Ballard should look elsewhere.