Anker battery issues

So why have a decent sized battery if I can't run it down to 50% during the day and recharge it overnight? Seems we're worried too much about an amperage and voltage drop that's barely 20% of rated capacity in a device designed to be charged and discharged repeatedly.

Sure makes the case to me that the SLA may still be the way to go for running electronics on a kayak vs. the overly costly lithium whatevers.

So why have a decent sized battery if I can't run it down to 50% during the day and recharge it overnight? Seems we're worried too much about an amperage and voltage drop that's barely 20% of rated capacity in a device designed to be charged and discharged repeatedly.

Sure makes the case to me that the SLA may still be the way to go for running electronics on a kayak vs. the overly costly lithium whatevers.

+1  all this tech data makes my brain ache but you guys are doing a bang up job on covering all the basics as well as the not so basics.

So why have a decent sized battery if I can't run it down to 50% during the day and recharge it overnight? Seems we're worried too much about an amperage and voltage drop that's barely 20% of rated capacity in a device designed to be charged and discharged repeatedly.

Sure makes the case to me that the SLA may still be the way to go for running electronics on a kayak vs. the overly costly lithium whatevers.

SLA have been shown to work just fine for electronics in kayak use - what this thread shows is that the newer li based technologies show much promise to significantly improve the cost per available WH/mAH - in a much smaller package.  With all of the gear that I'm loading and unloading every time I go fishing, not lugging the boxed up SLA has been great!

-Sam

Sorry for slow response. Been temporarily blind for the last 3 days due to a retina repair. Need a minute to catch up. 

So just before I had to abandon this thread for a few days, I sent this to one of our esteemed mbers,who also happens to be a budding electrical engineer. He asked me to share.

Enjoy

Quote from: [WR] on March 01, 2016, 10:44:03 PM
Rather than start a flame war I redacted this part:

I read back through the thread and it seemed that weight was a driving common factor of changing to the non SLA batteries .
I also realized that the majority of those advocating for the dry batteries are proudly Hobie drivers. I have to wonder if many of them are worried about weight because they are reaching the operating weight limits of their Outbacks and this is an attempt to buy their way out of that predicament instead of reducing on tackle or other things like Go Pros.

This doesn't mean I haven't learned anything here. In fact I learned a lot. And its somewhat fun to watch the EE boys geek out over a battery and how its built and discharges. But I still have to question motivation and sanity here because in the end its,just a battery.


His response:
BAAAhhh-ha-ha-ha-ha!!! 

I think what Sam is eluding to is that it is exhausting hauling all the fish and crab we catch up the beach to unload into the coolers. Therefore, loosing some extra pounds in the battery is a welcomed thing.

His response is good,  I don't know anyone near their weight limit on their Hobie. I do notice people constantly looking to disparage Hobies and their owners though.

I keep reading the technical specifications on all sorts of lithium-based batteries, reading manufacturer's guides, studying the technical papers coming out of universities... and none of them agree with each other.  The data, the specs and the manuals are all over the place.

No offense.  I'm doing this for my personal knowledge, not to catch anyone out.

I'm glad some of the NWKA members are taking the time to do some bench testing.  Thank you folks.

I have to disagree with the one conclusion that lithium batteries offer a better ratio of available energy-to-cost than other batteries.  That would be true if you were just buying a battery, but fails to include the cost of rigging it for kayak use.

You could, hypothetically, twist the wires to the terminals of an SLA, drop it into the kayak, and go fishing.  Until the terminals and(or) wires corroded-away.

To use lithium-ion or lithium-polymer batteries, you have to include the cost of keeping them dry or it's a false cost comparison.  Even a cheap solution for keeping the battery dry costs as much as the battery itself cost.

I'm a lot more interested in information about available energy per ounce, since cost-per-watt-hour has to include some arbitrary, but reasonable, estimated cost for the necessary battery compartment.

LOL - All good points.   And I agree it doesnt work on a stored power to cost ratio alone.    But here's the thing - I have taken to putting even an SLA in a dry box as I hate the corrosion that comes with leaving it free in the bilge or a dry-bag-that-isnt quite dry.  So my battery boxes  are a sunk cost, and I can easily adapt any of the batteries I have tested so far into those boxes.   I really like the specs (stored power to weight ratio and the discharge profile for voltage range primarily) for the LiFePO batteries, and two of the form factors will fit my existing boxes, but still haven't crossed over to actually break out my wallet and buy one at the  $120+ price point - for me it's adding the price to the equation that doesn't compute (yet).   Trade-offs, /sigh.   Hoping with more production the price comes down.

I have also have yet to find the cost of providing a waterproof box to be an issue.  I think I found these 2 for $10 on sale at Wallyworld. 



No doubt some have made some very trick battery boxes which were not cheap, but like myself I am sure they did so for the fun of it.  The box I am working on now has features like digital voltage and current draw displays and an alarm to tell me if water has entered into my kayak.  Just when I think my box will claim the title of "King of Bling" I see post of others who have raised the bar with their creative ingenuity  and I am back to the drawing board.  Odd what those of us who enjoy this stuff call fun I guess 

The battery box I put together for my SLA is a classic simple affair using a Lexan dry box from Freddies, some red and black 18 gauge wire, an inline  sealable marine fuze holder and a trailer connector. Added some closed cell foam to keep the battery snug in the box, and that's it. Works great when I use it on my T15 tucked into the bow.

Guys, geek out all you want. It's,your right to do so. It's good reading and there's plenty of tips,for those who know,what to look for. I'll stick with what I know. 

  Wow

 I can't believe the mileage on this post.
 But I am a pretty simple type guy.
 I use what works...........

Yeah, I popped an SLA into a dry box that was/is meant to hold blue bricks (whenever they get here) and it's a simple affair, but it isn't absolutely necessary for the SLA in the same way it is for lithium-based batteries.  Even the simplest construction using Wally World boxes on sale requires sealant, wires, a fuse holder, a fuse... and time, and even if all the bits-and-pieces were sitting in a box on the workbench, we paid for them at some point and the small costs do add up.

That aside, I agree that the test results for true available power, stored power to weight ratio, and the discharge profiles are all really valuable information, and I'm grateful to those who are providing it.

I, too, have not plunked down the big bucks for a LiFePO4 battery.  If I'd known how slow the slow boat from China can cruise, and if I hadn't purchased an SLA to hold me over, I might have gone LiFePO4 to begin with.  For now, LiFePO4 will wait until the SLA is a paperweight because, gee! how many different batteries does one need at one time?

Thanks, again.

I finally want to chime in and add "beware of low cost//cheap Lithium-ion batteries".....one has to remember the "Hoverboards" and many other devices that have caught fire while not plugged into the charger.
In a plastic boat, a battery that catches fire could have tragic results. It's for this reason I use SLA's.

But here's the thing - I have taken to putting even an SLA in a dry box as I hate the corrosion that comes with leaving it free in the bilge or a dry-bag-that-isnt quite dry.

Do you think the moisture your getting in your battery drybag could be condensation or is it just a leaky bag? I was experiencing something similar and made me nervous with mu LiFePo4. I have all good sealed and gooped connections and never became a problem per-se. Now I just connect it and set it in a tub-trug in the front hatch.