question

brucevanderbilt avatar image
brucevanderbilt asked

Lynx Power In vs Distributor Fusing Requirements for Lithium Batteries

Many Victron diagrams show Lithium batteries connected to a Lynx distributor using a MEGA fuse. A number of online resources seem to indicate that MEGA fuses are not safe for Lithium batteries. And that a class T fuse is the best option. Victron smart lithium battery manuals do not specify. Is there any kind of Victron guidance here. For example, should I use the Lynx Power In and Class T fuses on the battery cables, or am I safe using the appropriately sized MEGA fuses for my Victron Lithium batteries? My system has 4x 330ah 12v batteries.

Lithium Batteryfuses
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

3 Answers
steffen-graap avatar image
steffen-graap answered ·

Fuses are not to protect the equipment, but to protect the cables.

The protection of the lithium battery must be guaranteed by a BMS.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

Why shouldn't a Mega fuse be safe for lithium batteries?

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

egenolf avatar image
egenolf answered ·

Mega fuses when suddenly loaded with a full shortcut (2000 amps or so) will litterally explode, which may result in some collateral damage. A T type fuse has e ceramic enclosure that prevent such damage.

if the mega fuse is surrounded by an insulating and fireproof enclosure that limits the effect of flying hot debris it may be acceptable.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Related Resources

Fuses & fuse holders Product Page.


Additional resources still need to be added for this topic

Additional resources still need to be added for this topic