Safe to charge via USB phone on Controller without Battery?

OM617YOTA

Solar Enthusiast
The battery is the easy way. It's your solar time machine. It can be collecting energy while you and your phone are off doing whatever, and then let you charge your phone when convenient, regardless of what the sun is doing at that moment.

It's also only two extra wires.
 

saxon11

New Member
The battery is the easy way. It's your solar time machine. It can be collecting energy while you and your phone are off doing whatever, and then let you charge your phone when convenient, regardless of what the sun is doing at that moment.

It's also only two extra wires.
What if i plan to use by phone as a hotspot for 24/7 (another words i'd like to have it run without me all the time)
 

chrisski

Photon Sorcerer
Here’s what I did with no battery, but used a DC to DC converter and a USB Charging socket:


This is good for sitting around the RV and recharging devices as I use them. One a sunny day, the 100 watt panel can handle up to 6 amps of 12 volt chargign, but on a cloudy day, 1 amp or less. Each device takes up to an amp of power. More power when the battery is close to dead.

EDIT: I would not recommend this for a hotspot 24/7. I would definitely use a battery for that. Anyway, 24/7 would require a battery.
 

eabyrd

Solar Enthusiast
Some charge controllers require you to hook up the battery first to hold in the magic smoke. Without the battery hooked up when you connect the solar panels the magic smoke will escape rendering the charge controller unusable. I looked at the description of the one you linked to above, but I can’t say definitively if this one requires a battery or not. It does indicate that you should hook up the battery first and then add the panels, so I think it probably does.
 

OM617YOTA

Solar Enthusiast
You might get away with it, but I would definitely use a battery in that application, even if it's just a booster pack USB battery.

Is the hotspot the ONLY thing you'll be running? If you ever even might run something else, like the inverter referenced in your first post, you'll definitely need a battery.
 

12VoltInstalls

Solar Addict
hotspot the ONLY thing you'll be running? If you ever even might run something else, like the inverter referenced in your first post, you'll definitely need a battery.
A 50-70Ah usable (depending on who is telling you) Grp 27 Deep Cycle at walmartha is <$70 and that’s enough to actually do something. A Giandel 300W true sine wave is ~$60 snd will run cordless drill battery chargers and a soldering iron. Or the stupid leftover laptop I have that says something stupid and nonsensical like “21V” on it’s charger so my 12V can’t direct connect to it….
 

eabyrd

Solar Enthusiast
I have carried one of these backpacking for years. I have a friend who uses one for a trail cam. $65 on Amazon gets you what you need to keep a low power device running 7/24

Voltaic Systems Arc 10 Watt Rapid Solar Panel Charger | Includes a Battery Pack (Power Bank) and 2 Year Warranty | Powers Phones Compatible with iPhone, Tablets, USB Devices and More​


 

chrisski

Photon Sorcerer
I looked at the description of the one you linked to above, but I can’t say definitively if this one requires a battery or not.
The DC to DC converter listed does not require a battery. I used that for four days camping, and will start again once the weather cools.

Once you start dealing with no batteries, I wonder how the phone deals with surging throughout the day. I put that together with a 12 - 24 VDC USB charger, which may take the panel straight, but I put a DC to DC voltage converter to hold the voltage steady. That way if the DC to DC converter failed, the USB still regulates the power from the panel.

A 10 watt panel like linked could charge it, but with using the phone 24/7 as a wi-if router, I’m not sure if it would charge it enough. I find my phone uses 1 amp (12 watts) when charging, and after charged charged drops to .2 amps - ,3 amps if I’m using it. I don’t know how that would do throughout the night. The 100 watt panel you have would provide charging power throughout all but the cloudiest days.

It’s just figuring out how much energy you need to last through the worst cloudy stretch of days for the year or the shortest winter days.
 

eabyrd

Solar Enthusiast
The DC to DC converter listed does not require a battery. I used that for four days camping, and will start again once the weather cools.

Once you start dealing with no batteries, I wonder how the phone deals with surging throughout the day. I put that together with a 12 - 24 VDC USB charger, which may take the panel straight, but I put a DC to DC voltage converter to hold the voltage steady. That way if the DC to DC converter failed, the USB still regulates the power from the panel.

A 10 watt panel like linked could charge it, but with using the phone 24/7 as a wi-if router, I’m not sure if it would charge it enough. I find my phone uses 1 amp (12 watts) when charging, and after charged charged drops to .2 amps - ,3 amps if I’m using it. I don’t know how that would do throughout the night. The 100 watt panel you have would provide charging power throughout all but the cloudiest days.

It’s just figuring out how much energy you need to last through the worst cloudy stretch of days for the year or the shortest winter days.
The issue I had with phones was related to, but not exactly like surging. What happened was that the phone would stop charging when clouds came over & the voltage dropped, but then not start-up again when the clouds moved on. There were also times when the phone wouldn't charge at all during overcast periods. That's why I went with the Voltaic rig. Their batteries are optimized to charge even while discharging allowing them to be buffer between the panel & device. Many other USB battery banks don't allow for charging & discharging at the same time.

I can drape the panel off of my pack, run a USB cable down the pack to my waist pouch where the battery gets tucked in. I then wire my phone, or my headlamp, or whatever I'm recharging to the battery & tuck it into another pack pocket or my pant's while it charges. That way I can charge while walking and it doesn't matter if I walk through shade or sun, forest of field. My rig came with a 4AH battery instead of the larger ones offered now so I have run tight on consecutive cloudy days, but its really only the phone & my fit-bit that need recurring charges, kindles and lights carry enough charge for weeks on end
 
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