Lithium-ion batteries are an indispensable component of numerous contemporary applications, such as electric vehicles and renewable energy systems. However, accurately predicting their remaining service life is a significant challenge due to the complexity of degradation patterns and time series data. To tackle these challenges, this study introduces a novel Multi-Scale Time Attention (MSTA) mechanism designed to enhance the modeling of both short-term fluctuations and long-term degradation trends in battery performance. This mechanism is integrated with the Bidirectional Gated Recurrent Unit (BiGRU) to develop the BiGRU-MSTA framework. This framework effectively captures multi-scale temporal features and enhances prediction accuracy, even with limited training data. The BiGRU-MSTA model is evaluated via two sets of experiments. First, using the NASA lithium-ion battery dataset, the experimental results demonstrate that the proposed model outperforms the LSTM, BiGRU, CNN-LSTM, and BiGRU-Attention models across all evaluation metrics. Second, experiments conducted on the CALCE dataset not only examine the impact of varying time scales within the MSTA mechanism but also compare the model against state-of-the-art architectures such as Transformer and LSTM–Transformer. The findings indicate that the BiGRU-MSTA model exhibits significantly superior performance in terms of prediction accuracy and stability. These experimental results underscore the potential of the BiGRU-MSTA model for application in battery management systems and sustainable energy storage solutions.