From the mains, by the maximum input wattage the unit accepts, which some models let you reduce to be gentler on the cells. From solar, by whichever is smaller: the panel’s real output at that moment or the station’s solar input limit.
Recharge speed is now a headline specification, and it is governed by limits at both ends of the cable.
The mains side
The station publishes a maximum input, and that is the ceiling regardless of what it is plugged into. What actually arrives can be lower: the supply, the extension lead and the unit’s own temperature management each intervene.
The solar side
Two numbers compete. The station has a maximum solar input — a wattage, a current and a voltage window, all three of which matter — and the panels have whatever they are producing under the sky of the moment, which is rarely their rating. The smaller number wins, and it is usually the sky.
Why the voltage window decides more than the wattage
A panel string below the minimum will not start the charger at all, whatever its wattage; a string above the maximum risks the input. This is why two panels that add up to the right wattage can still fail to charge a station, and why the window is the specification to check first.
What the last stretch costs
Charging slows markedly near full, on every lithium chemistry, because the current tapers. A quoted time to eighty per cent and a quoted time to full describe very different parts of the same curve, and comparing one against the other is comparing nothing.
Where this page and the manufacturer’s documentation differ, the documentation is the one to follow. Every capacity, output, input window, current limit, cycle count and temperature threshold on this page comes from the maker’s own published figures, with the unit as printed and the source named. None of it is measured here, and no figure is converted into another convention, because a converted number is a different number. And the distinction this page keeps: a nominal capacity is not the energy that reaches a socket. A reserve the chemistry never gives up, and the cost of converting stored direct current into a mains-style output, both sit between the two. Where a maker publishes a usable figure, this page reports it beside the nominal one; where only the nominal one exists, it says so rather than converting it.
What people ask before they order
Why would anyone slow the charging down?
Because heat and high charge rates shorten cell life, and several makers offer a reduced-rate mode for exactly that reason. The manual states what the mode changes.
Can mains and solar charge at the same time?
On some models, and they publish a combined figure when they do. On others the inputs are exclusive, and the listing says which one takes priority.
Last reviewed 16 September 2026