Exhibit 31.2

CERTIFICATION

I, Han Yongbin, certify that:

| 1.     | I have reviewed this Amendment to the Quarterly   Report on Form 10-Q/A of China BAK Battery, Inc. for the period ended   December 31, 2005;                                                                                                                                                                                                                             |
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| 2.     | Based on my knowledge, this Amendment to the   Quarterly Report on Form 10-Q/A does not contain any untrue statement of a   material fact or omit to state a material fact necessary to make the   statements made, in light of the circumstances under which such statements   were made, not misleading with respect to the period covered by this   quarterly report; |
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| 3.     | Based on my knowledge, the financial statements, and   other financial information included in this Amendment to the Quarterly   Report on Form 10-Q/A, fairly present in all material respects the financial   condition, results of operations and cash flows of the registrant as of, and   for, the periods presented in this quarterly report;                      |
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| 4.     | The registrant’s other certifying officer and I are   responsible for establishing and maintaining disclosure controls and   procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the   registrant and we have:                                                                                                                                |
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|   | (a)                                                                                                                                                                                                                                                                                                                                                                      | Designed such disclosure controls and procedures, or   caused such disclosure controls and procedures to be designed under our supervision,   to ensure that material information relating to the registrant, including its   consolidated subsidiaries, is made known to us by others within those   entities, particularly during the period in which this quarterly report is   being prepared; |
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|   | (b)                                                                                                                                                                                                                                                                                                                                                                      | Evaluated the effectiveness of the registrant’s   disclosure controls and procedures and presented in this report our   conclusions about the effectiveness of the disclosure controls and   procedures, as of the end of the period covered by this report based on such   evaluation; and |
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|   | (c)                                                                                                                                                                                                                                                                                                                                                                      | Disclosed in this report any change in the   registrant’s internal control over financial reporting that occurred during   the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal   quarter in the case of an annual report) that has materially affected, or is   reasonably likely to materially affect, the registrant’s internal control   over financial reporting; and |
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| 5.     | The registrant’s other certifying officer and I have   disclosed, based on our most recent evaluation of internal control over   financial reporting, to the registrant’s auditors and the audit committee of   registrant’s board of directors (or persons performing the equivalent   functions):                                                       |
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|   | (a)                                                                                                                                                                                                                                                                                                                                                                      | All significant deficiencies and material weaknesses   in the design or operation of internal control over financial reporting which   are reasonably likely to adversely affect the registrant’s ability to record,   process, summarize and report financial information; and |
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|   | (b)                                                                                                                                                                                                                                                                                                                                                                      | Any fraud, whether or not material, that involves   management or other employees who have a significant role in the registrant’s   internal control over financial reporting. |