Lithium manganate and preparation method and application thereof

The invention belongs to the field of materials, and relates to lithium manganate and a preparation method and application thereof. The preparation method of the lithium manganate comprises the following steps: preparing metal salt into a metal salt solution with the conductivity of more than or equal to 200uS/cm, and then carrying out chemical corrosion crystallization reaction on manganese metalelementary substance and/or manganese metal oxide, a doping agent, an oxidant, water, an ammonia-containing solution and the metal salt solution under the conditions that the oxidation-reduction potential ORP value is less than or equal to -100mv, the complexing agent concentration is 3-50g/L and the conductivity is more than 200uS/cm; and sequentially carrying out magnetic separation, solid-liquid separation, washing and drying, mixing with a lithium source, and calcining. When the method provided by the invention is used for preparing the lithium manganate, no wastewater is generated in thedissolving and crystalliz