The present invention provides an olivine-type positive active material precursor for a lithium battery that includes MXO.sub.4-zB.sub.z (wherein M is one element selected from the group consisting of Fe, Ni, Co, Mn, Cr, Zr, Nb, Cu, V, Ti, Zn, Al, Ga, Mg, B, and a combination thereof, X is one element selected from the group consisting of P, As, Bi, Sb, and a combination thereof, B is one element selected from the group consisting of F, S, and a combination thereof, and 0z0.5) particles, and the precursor has a particle diameter of 1 to 20 m, a tap density of 0.8 to 2.1 g/cm.sup.3, and a specific surface area of 1 to 10 m.sup.2/g. The olivine-type positive active material prepared using the olivine-type positive active material precursor has excellent crystallinity of particles, a large particle diameter, and a high tap density, and therefore shows excellent electrochemical characteristics and capacity per unit volume.

The present invention provides an olivine-type positive active material precursor for a lithium battery that includes MXO.sub.4-zB.sub.z (wherein M is one element selected from the group consisting of Fe, Ni, Co, Mn, Cr, Zr, Nb, Cu, V, Ti, Zn, Al, Ga, Mg, B, and a combination thereof, X is one element selected from the group consisting of P, As, Bi, Sb, and a combination thereof, B is one element selected from the group consisting of F, S, and a combination thereof, and 0z0.5) particles, and the precursor has a particle diameter of 1 to 20 m, a tap density of 0.8 to 2.1 g/cm.sup.3, and a specific surface area of 1 to 10 m.sup.2/g. The olivine-type positive active material prepared using the olivine-type positive active material precursor has excellent crystallinity of particles, a large particle diameter, and a high tap density, and therefore shows excellent electrochemical characteristics and capacity per unit volume.

The present invention provides an olivine-type positive active material precursor for a lithium battery that includes MXO.sub.4-zB.sub.z (wherein M is one element selected from the group consisting of Fe, Ni, Co, Mn, Cr, Zr, Nb, Cu, V, Ti, Zn, Al, Ga, Mg, B, and a combination thereof, X is one element selected from the group consisting of P, As, Bi, Sb, and a combination thereof, B is one element selected from the group consisting of F, S, and a combination thereof, and 0z0.5) particles, and the precursor has a particle diameter of 1 to 20 m, a tap density of 0.8 to 2.1 g/cm.sup.3, and a specific surface area of 1 to 10 m.sup.2/g. The olivine-type positive active material prepared using the olivine-type positive active material precursor has excellent crystallinity of particles, a large particle diameter, and a high tap density, and therefore shows excellent electrochemical characteristics and capacity per unit volume.

The electrochemical reactors disclosed herein provide novel oxidation and reduction chemistries and employ increased mass transport rates of materials to and from the surfaces of electrodes therein.