Thran Dynamo

Always crafted from smooth bronze, steel, or platinum, these portable generators are based on ancient magical artifice and can convert mechanical energy into pure magical energy. The dynamo can hold up to 3 charges and has a small hand crank on one side. You can spend an hour cranking the handle, only pausing for up to a total of 10 minutes, in order to cause the dynamo to gain 1 charge. Once the dynamo is charged, you can use an action to expend any number of charges in order to regain a number of expended spell slots with a total level equal to or less than the number of charges stored in the dynamo. Once the dynamo is charged, its charges slowly drain away into the air around it, causing the dynamo to lose 1 unused charge every 24 hours. Alternatively, the dynamo can be integrated into the movement system of any vehicle in a process which takes 8 hours and must be done by someone with proficiency in the use of that vehicle. Once the dynamo is integrated, it no longer passively loses charges, and it can not be used to regain spell slots, though it still gains charges in the same way. Any creature piloting a vehicle with an integrated dynamo can use an action and expend a charge from the dynamo to cause the vehicle’s speed to double for 1 hour.