Samsung was too "aggressive" in the design of its now-recalled fire-prone Galaxy Note 7 devices, particularly when it came to installing its battery, a new report claims.

The South Korean electronics giant was forced to recall and stop production of the Note 7 phones after reports of them exploding and setting alight. Samsung is yet to identify a reason for the issue publicly.

But one manufacturing technology company called Instrumental performed a teardown of the handset and thinks it has come up with the cause of the phablet's problems.

The battery in the Note 7 is made up of a positive layer made of lithium cobalt oxide, a negative layer made of graphite, and a layer to separate those two materials. The layer in the middle allows energy to flow between the positive and negative layers. But if those layers touch, it would cause the battery to heat and that could lead to an explosion, according to Instrumental.