IEC 62485-4:2015 applies to the safety aspects associated with the accommodation, the arrangements of circuits and the operation of secondary valve-regulated lead-acid cells and batteries in portable appliances. Requirements are specified which oblige the manufacturers of appliances and secondary batteries to prevent the misuse of batteries in the course of operation to provide protective measures avoiding injury to persons in case of battery failure and to provide sufficient information to users. This standard does not apply to secondary cells and batteries containing alkaline or other non-acid electrolytes. This first edition cancels and replaces the first edition of IEC TR 61056-3 published in 1991. It constitutes a technical revision. This edition includes the following significant technical changes with respect to the IEC TR 61056-3: a) updating of the requirements, and harmonisation of the text for consistency with the IEC 62485 series.