Sel litium ion (Li-ion) telah digunakan dalam kebanyakan barangan di sekeliling kita seperti telefon bimbit, komputer riba, kamera digital dan lain- lain peranti elektronik dan kebelakangan ini terdapat banyak permintaan aplikasi dengan bateri penggunaan yang lebih tinggi seperti hibrid dan kenderaan elektrik (HEV). Selari dengan penggunaan aplikasi yang semakin meluas, bateri-bateri yang mempunyai ketahanan yang tinggi di perlukan beserta persembahan kualiti yang tinggi. Sistem pengurusan bateri perlu menambahbaik prestasi bateri yang semakin bertambah permintaan supaya berupaya untuk menggunakan bateri secara keseluruhan. Beberapa kaedah diperkenalkan bagi memantau prestasi bateri dengan meramalkan keadaan kesihatan (SoH) bateri yang biasanya dipengaruhi oleh kadar kapasiti bateri. Penambahbaikan kaedah telah dicadangkan dalam meramal keadaan kesihatan(SoH) dengan menganalisis dan menyiasat parameter yang menjejaskan prestasi sel bateri. Kajian terhadap keadaan kesihatan (SoH) telah memberi tumpuan tinggi kepada tiga parameter iaitu suhu, kapasiti bateri dan bilangan kitaran. Pengurangan nilai kapasiti bateri dan suhu membawa kepada penurunan dalam peratusan keadaan kesihatan (SoH) kerana bateri litium ion menjalani proses penuaan pada setiap kitaran caj dan nyah-caj. Apabila berlakunya pengurangan kapasiti, kemudian berlakunya peningkatan kitaran sepanjang masa yang terjadi. Berdasarkan kepada keputusan, dapat disimpulkan bahawa ketiga-tiga parameter adalah penting dalam menunjukkan keadaan kesihatan bateri sama ada bateri masih boleh beroperasi atau tidak kerana bateri lithium-ion mengalami kemerosotan dari masa ke semasa.
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Lithium ion(Li-ion) cell have been used in almost everything around us such as cell phones, laptop computers, digital cameras and in many other electronic devices and nowadays there are more demanding applications with higher usage battery like Hybrid and Electric Vehicle (HEV). With bigger application, we need more reliable batteries as well as higher quality in their performance. Battery management system needs to be improve the performance of the battery with such high demands to be able deliver the full use of the battery cell. Several methodologies have been introduced to monitor the performance of battery by predicting the State-of Health (SoH) of the battery that generally affected by the rate of battery capacity. The improve methodology is proposed in predicting the State-of-Health (SoH) by analysing and investigating the parameters that affected the battery cell performance. The study of State-of-Health (SoH) estimation is more focusing on three parameters which are temperature, capacity of the battery and number of cycle. The reduction on the value of battery capacity and temperature led to decreasing in percentage of State-of-Health (SoH) because the lithium-ion battery undergoes aging process at each charge-and –discharge cycle. When the capacity decrease, then number of cycle increase as time passes. With these results, it can be concluded that these three parameters are crucial in indicating the health condition of the battery whether the battery still can operate or not since lithium-ion battery undergoes degradation as time passes.
State-of-health prediction of lithium- ion battery cell in an electric vehicle / Nurakmal Laili Mohd A’shri