It’s not always possible nor desired to wait until a solar generator has fully recharged its battery bank before you can use it again.
During a blackout or when you are outdoors, it can be inconvenient to wait hours until the solar generator has recharged before you can charge your phone or plug in the mini fridge.
For this reason, most solar generator manufacturers have designed their power stations to be used safely while they are charging from solar, AC or your vehicle.
This is called pass-through charging. While convenient, it comes with some downsides.
And not all solar generators handle this situation in the same way, however. Some limit the input power source to solar alone. And you may encounter limitations such as a reduced output power during charging and a reduced battery discharge window.
How Does Pass-through Charging Work?
A solar generator with pass-through charging allows power to ‘pass-through it’ to whatever is plugged in.
The power coming from the solar panels or an AC outlet charges the solar generator battery while at the same time powering/charging a plugged-in appliance or device.
That means you don't have to wait until the solar generator battery is 100% charged so that you can charge your phone, connect lights, or power the TV.
Do All Solar Generators Have Pass-through Charging?
Most modern solar generators from major brands like Goal Zero, Jackery, Bluetti and EcoFlow have pass-through charging.
The only way to be sure is to check your solar generator’s manual or ask the manufacturer. Some older solar generator models may not have this feature.
The manual will also include warnings, advice and anything else you need to note about using your solar generator while it’s charging.
Normally, you don't have to do anything special to turn on pass-through charging. If you are charging your solar generator and you plug in a device or appliance, the power station will automatically provide pass-through charging.
5 Things To Note About Pass-through Charging
1. It might make the power station warmer, but it’s safe
If you’ve ever charged a power bank while it’s charging your phone at the same time, you may have noticed that it gets a bit warm. It’s actually the battery that heats up.
The same thing happens in a solar generator. Charging already generates heat in batteries. When you plug in an appliance, some of the power is diverted from the battery, meaning charging takes longer.
This generates additional heat, causing the battery and the solar generator to get warmer.
Don't worry if this happens to your solar generator. Solar power stations have all sorts of safety measures to prevent overheating and battery damage.
Slight warming up is not a big deal in terms of safety. It can, however, affect battery lifespan. More on that shortly.
2. Your solar generator will take longer to recharge
When you use a solar generator while it’s charging, you are taking away some of the power that would have gone towards charging the battery.
So the solar generator will take longer to recharge. An easy way to see this for yourself is to check the estimated recharge time on the solar generator display.
When you plug in an appliance or a gadget like your phone, that estimated time will go up.
If you want to charge the solar generator as quickly as possible, it’s best to avoid using it while it’s charging.
3. It might reduce your solar generator lifespan
The biggest enemy of lithium batteries is heat. Prolonged exposure to heat reduces the lifespan of a battery, and thus the solar generator.
We’ve already discussed how pass-through charging generates more heat in the battery.
If you only occasionally use your solar generator while it’s charging, the impact on battery lifespan is minimal.
But if you do it constantly, the heat build up in the battery could reduce the lifespan of the solar generator.
Tips For Using Pass-through Charging
Most reputable solar generator brands these days allow pass-through charging. It’s also totally safe to use most solar generators while they are charging.
That said, for the best solar generator lifespan and performance, use this feature sparingly and follow manufacturer instructions.