Due to the high costs of long-term testing and discrepancies between real-world operating conditions and laboratory environments
labeled data for lithium-ion battery state-of-health (SOH) estimation remains scarce. To address this challenge
this study proposes a semi-supervised SOH estimation method based on self-convolutional neural network (CNN)-transformer with loss regularization (SCT-LR). First
health indicators are extracted through incremental capacity analysis
and a CNN-Transformer hybrid architecture is employed for establishing a mapping model between these indicators and SOH. Second
this paper adopts a self-training semi-supervised learning framework to generate pseudo-labels for unlabeled samples
enabling iterative annotation and utilization of unlabeled data. Finally
to mitigate the impact of label noise in pseudo-labels
this paper introduces a semi-supervised prediction method incorporating a label noise learning module with loss function regularization. The results demonstrate that the proposed method significantly improves SOH estimation accuracy by leveraging unlabeled data. Specifically
it achieves a 12.11% or greater improvement in estimation accuracy compared to supervised learning benchmarks
while the integration of the label noise learning module reduces the average error by 14.41%. This work provides a robust framework for accurate battery SOH prediction in real-world scenarios with limited labeled samples.