This disclosure provides systems, devices, apparatus and methods, including computer programs encoded on storage media, for wireless power transmission. In accordance with this disclosure, a wireless power transmission apparatus (such as a charging pad) may support positional freedom such that a wireless power receiving apparatus may be charged regardless of positioning or orientation of the wireless power receiving apparatus. Various implementations include the use of multiple primary coils in a wireless power transmission apparatus. The multiple primary coils may be configured in a pattern, size, shape, or arrangement that enhances positional freedom. In some implementations, the placement of the multiple primary coils may optimize the size and distribution of electromagnetic fields that are available to charge a wireless power receiving apparatus.