Electrophysiological recording and neural stimulation in freely moving laboratory mice offer significant potential for advancing in neuroscience research, enabling the study of neural activities and brain functions in natural surroundings. Using wireless technologies and miniaturized devices, researchers can monitor and manipulate the electrical activity of neurons in real time while the animals engage in complex behaviors. However, depending on its size and weight, the autonomy of a wireless system is limited to a few minutes or a few hours at most. To address this, a wireless link for continuous power transmission is essential to run practical experiments. Working with mice is challenging due to their small size and limited volume available, necessitating the use of very small coils. It is also crucial to maintain the Specific Absorption Rate (SAR) within safe limits to prevent heating and temperature rises that could interfere with physiological conditions and measurements. This paper introduces a methodology to design an optimized overlapping multi-coil array integrated within a standard homecage, featuring a high-quality factor design that effectively couples with a small, lightweight receiver coil for in-vivo measurements with laboratory mice. Using trace adjustment, the transmitter design enhances the self-resonance frequency (SRF) of the coils, resulting in an improved quality factor, with measurements indicating a value of 173 at 6.78 MHz. Using a 0.46-gram, 14-mm receiver (RX) coil, the measurement results reveal a maximum power transfer efficiency (PTE) of 7.5% and a maximum power delivered to the load (PDL) of 23.8 dBm (240 mW) at a 4-cm distance. Additionally, continuous in-vivo recording sessions demonstrate the delivery of approximately 46 mW on average wirelessly to the battery using a 0.4-gram, 16-mm RX coil installed on the head of a laboratory mouse. The system also prevents thermal effects in mice tissues, with a peak spatial-average SAR (psSAR) of 1.75 W/kg, which is well below the standard regulatory limits.