Standards
The standards behind the figures on a battery
Most figures on a battery, a panel or an inverter come from documents other people wrote: a cell safety standard, a set of test conditions, a transport test, an enclosure rating, a connector designation. Those documents are precise, and several things sold here as standards are conventions with no publisher at all. Each page says which it is, in four parts — what the body defines, what it does not promise, what it works with, and which families on this site rely on it.
Batteries & cells
The safety standard cited on lithium cells and the transport tests a pack passes before it may be shipped — what each one tests, and what it says nothing about.
Photovoltaic
The conditions a panel rating is measured under and the accelerated sequence a module design has to survive, read as laboratory figures rather than as forecasts.
Electrical safety
The safety standard for photovoltaic converters and the marking a manufacturer applies to declare conformity — who is making the claim, and what it covers.
Connectors & cable
The round solar connector that became a common noun, the two vehicle socket shapes, and the sizing systems cable is sold under on either side of the Atlantic.
Market conventions
Battery group sizes, enclosure ratings and wire colour habits: designations that fix a shape or a hint, and leave everything electrical open.