"Hybrid" lithium batteries contain both primary lithium metal cells and rechargeable lithium ion cells, that are not designed to be externally charged.
During the December 2015 session of the UN Sub-Committee of Experts for Transport of Dangerous Goods. some provisions concerning the carriage of these hybrid lithium batteries have been drafted. Although adoption of these provisions is still pending there is currently a need to transport such batteries.
M296 multilateral agreement proposes to apply those provisions under consideration by the sub committee by anticipation, enabling the carriage of these batteries on that basis.
These "hybrid" lithium batteries may be assigned to UN 3090 or 3091, as appropriate, for their carriage
The batteries shall meet the following conditions:
(a) the rechargeable lithium ion cells can only be charged from the primary lithium metal cells;
(b) overcharge of the rechargeable lithium ion cells is precluded by design;
(c) the battery shall be of a type that has been successfully tested as a lithium primary battery according to the Manual of Tests and Criteria, part III. sub-section 38.3;
(d) component cells of the battery shall be of a type proved to meet the respective testing requirements of the Manual of Tests and Criteria, part III, sub-section 38.3.
When such batteries are transported in accordance with Special Provision 188 the total lithium content of all lithium metal cells contained in the battery shall not exceed 1g and the total capacity of all lithium ion cells contained in the battery shall not exceed 20 Wh.
The M296 agreement have been signed by France, Germany and UK up till now and is valid in these coutries only.