It typically takes about 1 to 4 hours to fully charge a lithium-ion battery, depending on the device and charger used. Most smartphones fully charge in approximately 1.5 to 2.5 hours with a standard charger. In contrast, larger devices like laptops can take about 2 to 4 hours for a complete charge.
[pdf] Solar panels can charge lithium batteries, but an MPPT solar charge controller is required. More current goes into the battery when an MPPT controller is used, which leads to faster battery charging. This is a step by step guide to charging lithium batteries with solar panels.
[pdf] USB-C ports offer the fastest charging speeds and highest power delivery, making them ideal for modern lithium battery pack applications. Using certified USB cables and chargers ensures safe, reliable charging and protects your lithium battery packs from damage.
[pdf] 
