I used them with a PC laptop, and a Macbook Pro. They work much better with a Macbook Pro, but even that killed one after while. I have a PC laptop (HP dv6000 series) with an 8.8 amp-hour lithium battery (extended battery). This PC laptop can kill a SOLO 15 after the first use …

I’m guessing the SOLO 15 would be perfect for an Ipod Nano, or a regular cell phone, but definitely not as a backup for a laptop. The problem seems to be when you discharge them too much. That is unavoidable if you are charging up a laptop, unless you want to stand nearby to check the battery level on the SOLO 15 every five minutes, in order to disconnect it when it gets down to one bar of power.

Contrary to what some sales people claim about these batteries on other web sites selling these units (they say it can power a laptop for 6 hours), a laptop can drain a SOLO 15 completely within about 90 minutes, and then it’s slowly damaging the SOLO 15 by draining it too far. Apparently they do not have circuitry to prevent over-discharging.

It can indeed provide 6 extra hours of power to a Macbook Pro, if the Macbook Pro it turned off, and the SOLO 15 is hooked up and recharging the Mac’s internal battery. But it’s a gamble because sooner or later the SOLO 15 will be drained too much and will not be the same afterward.

I disagree with the other reviewer who said these batteries can be drained down to nothing without hurting them. I think that is what hurts them most, but that is unavoidable. It will happen eventually, and then you’ve thrown $300 down the drain.

The lesson I learned is to ONLY use batteries for recharging that are well protected from over-discharging.

Rating: 2 / 5

Because it is a lithium pack, rather than a lead-acid pack, you won’t hurt it at all if it drains down to empty. Whereas if you do that to a lead-acid battery, it won’t hold nearly the same charge from that point forward. Lithium polymer technology for rechargeable batteries is excellent in every technical parameter, and this Brunton device seemed to make the cost of that technology very competitive with other types of batteries, like lead-acid. Soooo … if the *flaws* get worked out with the SOLO 15 … then it will be something really special.

I received my first Brunton SOLO 15 last week from Amazon. It looked great, and its package included an array of sturdy cables & connectors, and a nice, quiet little inverter unit that is *not* built-in to the battery. That was a good idea, really, because that means you can use a different inverter if necessary. Inverters will sometimes fry, or debris will get into the cooling fan and make noise, etc. Good idea to keep the two components separate, if you’re wanting the most dependable system you can put together.

I would have expected the inverter to be the weak link in the chain, but it’s the battery pack that is so flawed.

I charged it up overnight. It had a full charge when I started using it, and it did keep my laptop going for a few hours, as expected. But when the power output level eventually started dropping I pushed the button on the face of the unit to show the battery level, while the unit was still plugged in to the laptop (the manual says you can do that) … then all the LEDs flashed at once, and then went out completely.

I tried charging up the unit overnight again, and it won’t hold a charge now. The green LED’s (showing the battery level) do not work at all. I would have been willing to live with it if the green LEDs merely didn’t work. I would have simply used my multimeter to check the batter level. But the whole unit is fried. Nothing works.

I did not expect this to happen with an expensive lithium-based power pack. Obviously there’s some weak parts in the main circuit board, based on my own experience, and what I gleaned from other reviews. The Chinese manufacturers apparently didn’t test these devices enough (not as much as an American manufacturer would have done) before mass producing them. The current iteration of SOLO 15 battery packs might work … but might have to be treated with kit gloves. Thankfully Amazon’s return policy makes it easy for me to send back the unit and receive a replacement without having to wait very long.

While I’m waiting I ordered another SOLO 15 pack. I planned on getting two of them originally. I want to make very sure that I’m not throwing out the baby with the bath water. I want to give these little devices a chance, and just assume I got a bad one. So I’ll soon have two brand new ones. I’m going to use them both a lot in the first 30 days to see if they fry before I am unable to get a refund.

I also ordered a Brunton Solar Panel (15 watt) and have received it and tested it a bit with a multimeter.

As with the Brunton SOLO 15 battery pack, the solar panel looks great, and it comes with nice sturdy cables and connectors … and it kicks out a lot of power for its size. The only flaw I have found with this panel is …. the power cord, specifically where it enters into the frame of the solar panel. The cord is very vulnerable and unprotected at that *protruding* part of the frame. It will fray and break eventually if the panel is moved around a lot.

I will be taking the solar panel(s) in and out of vehicles a lot, and bumping them around, and driving down bad roads with them, etc., so the vulnerable point of the cord needed to be reinforced somehow. I had to create and attach my own protector bracket in back of where the power cable enters the frame, to make sure the cord does not get tugged at that point. The cord is ALREADY starting to show the slight signs of weakening and fraying from too much bending and pulling … and that was after the first day of using it…. The outer sheath has pulled away, exposing the red and black wires of the power cord. Both wires are slighty kinked from having been tugged along the edge of the entry point into the frame.

My sense is the solar panel will not fail if the power cord does not fail. That would be nice. Keeping my fingers crossed.

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Update on the Brunton experiments.

First, regarding Brunton solar panels:

I have removed the two 15 Watt solar panels from my vehicle, and replaced them with one Solaris 52. I’ve tested them side-by-side in the bright California sun for a few days now. The Solaris 52 is fantastic. It is much better than 2 of the 15 Watt panels side by side. To think I’d need four (4) of those 15 watt panels to equal the output of one Solaris 52. The Solaris 52 is expensive ($650), but it is so versatile and stashable and powerful that I can’t imagine being without one now. I’ve recently ordered a second one.

Regarding the Brunton SOLO 15 battery … They are a bit too delicate.

One problem for Brunton is that some web sites claim the SOLO 15 battery can be used to power a laptop. They are really not designed for that. They can recharge a laptop pretty well, but running the laptop while the laptop battery is being recharged tends to drain it very quickly, and possibly even hurt it. Better off letting it recharge a laptop battery with the laptop off, then unhooking it from the laptop when running the laptop.

The bigger problem is something Brunton will need to address with a little slip of paper included in the box — a slip of paper warning users that although the manual claims you can power a device with the SOLO 15 *while* the SOLO 15 is being recharged … that can easily ruin these batteries if you’re powering a laptop. The folks at Brunton can check this themselves. I have damaged two of these batteries now by doing that: Powering a laptop while the SOLO 15 was being recharged by another 12v battery pack. The first time I was using the little included inverter. The second time I was powering a laptop with a 12v car adapter for the laptop.

After you use it that way the battery may still show that is has a charge, but it won’t take a charge anymore. The red LED does not even come on, and the little LED on the Brunton AC charger is blinking, indicating that there’s a problem charging the battery. I know that is what it means because I have two batteries and two AC chargers, so I can swap the charges between the one SOLO 15 that still works, and the one that is malfunctioning.

The absolute ideal portable laptop battery would be about the same size and shape as the SOLO 15, with perhaps more power, but better fault protection, even if that means accessible fuses. They should also consider adding a liquid crystal screen that could show charge level, and whether the input current or output current is too much or too little. Then it would be the perfect small portable 12v battery for taking into the field, or even taking around the house or the yard where there might be no AC outlets …

Rating: 2 / 5

An update: The 3rd one died too. After a little less than 1 months usage. Get the APC Mobile Power Pack instead.
Rating: 2 / 5