Recent content by jimster99

Hello! I'm back :) I am close to pulling the trigger on this project but want to be sure it's not going to break anything. Below is a diagram of what I plan to do (NB the lighter socket on my car is live even when the ignition is off and is 120w rated so I think it's fine to charge through it)...

As a starter for 10, here is what I have assembled thus far: My solar power panel & the three 5v USB outputs PortaPow USB amp/volt/amp hour meter that I will use to measure the draw once installed (very useful for testing USB cables and charging equipment - it retains memory even when power...

Thinking a bit deeper, isn't it possible to connect the three USB outputs of my solar panel together the way the dude in this video has done? I could just decrease the voltage further with a bigger resister, to hit the target float voltage? Then I wouldn't need any fancy electronics at all...

One other problem - apparently the float voltage for a lead acid battery varies significantly depending on air temperature . The car is usually stored in the UK, where temperatures range probably from -4c to 30c (and very ocasionally outside those ranges) but most commonly in the 5c to 20c...

Thanks @schism, I definitely will! As background context, I originally bought the 28w solar panel to use for camping trips but have found it impractical (primarily, it needs the angle adjusting too often, is floppy and has no kick stand so very hard to position correctly, is a bit too bulky to...

Thanks :) That makes sense. Would adding a charge controller into the equation help at all (to allow a full charge, if ever needed), or is that adding unecessarily complexity with no benefit? Also, my solar panel has 3 x USB 5v outputs. In theory, could I combine the three ports together in...

I've found some cheap solar power charge controllers on ebay (one example: https://www.ebay.com/itm/30A-Solar-Panel-Battery-Charge-Controller-12V-24V-LCD-Regulator-Auto-Dual-USB/224106938612?hash=item342dd080f4:g:~8kAAOSwQotfKwdY). Would it be better to link the following chain to offer better...

Thanks again for the link! Some of the comments to these step-up devices suggest they spike the output voltage to 30v+ when the input drops below the minimum 4v which - I assume - happens quite often for a solar panel. Is that a concern for a car battery? Obviously sustained high voltage would...

PS the schematic for the unit you linked says it needs 5.5v+ input, whereas my solar panel only puts out 5v. I assume that's a deal breaker for this particular unit?

Thanks Snoobler!! Appreciate the detailed and helpful reply :-) Your comment about not doing a normal profile charge makes a lot of sense, although presumably I could manually alter the voltage going into the battery (with caution) to do a full charge if that ever became necessary (although...

Hello all! This is my first ever post on this (awesome) site :) Experience level: I have a reasonable grasp of the theory of electricity (no problem comprehending volts/amp/watts) but am fairly lacking in real-world electronics skills. I have the following questions: Question 1: What gadgets...