I need some expert advice on battery power supply choices....

[mike(swWash)]

I want to run a couple bilge pumps that draw 14amps total to supply my high banker. I'll only need power for 4-5 hrs. and it might be used 6 times a year.

In the past I've used a cart and a 60lb. deep cycle battery (heavy sweating icon here).

Now I want to be able to put all my equipment on 2 backpacks and keep the power supply below 35lbs. to get to more remote spots.

Maybe one of the portable battery jumper things

 

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[Goldwasher]

Im not an expert but would a 56 ah battery get you 4 hours?...40 lbs UPS12-170FR C&D Technologies High-Rate Discharge Battery (12 Volt 56 Amp)

 

[Goldwasher]

Also 40lbs 12-180 NSB NorthStar Replacement High-Rate Discharge Battery (12 Volt 56 Amp) lbs........

 

[Anduril]

If the object is to reduce the weight, I would suggest looking at the bilge pumps first.

What is the make & model of the bilge pumps you are using now? (preferably from the nameplate ratings if they are present on the pump)
How many gallons of water per hour (or per minute) do you require for your setup?
What is the minimum flow you can live with?

Also, is the 4-5 hours continuous use, or intermittent use? (I'm assuming continuous use for those 4-5 hours - straight use, no on/off).

You are below about 0.84 kWh now, so let's see if we can improve that before sizing batteries.
Are you totally against engine power? (Just wondering. Not convinced it will reduce weight until we see the specs & your flow requirements.)

This is just about the power budget right now.
Please table any concerns regarding reliability for the moment.
We will not allow those to get swept under the rug!

 

[Timberdoodle]

The only battery powered option I know of to get you reduced weight (under 35lbs) and supply the power you need for 4-5hrs is Li-ion phosphate. A single 35ah can weigh only 4lbs vs a 35ah SLA battery that weighs 24lbs. Running two 35ah batteries would do the job for about 4hrs. Problem is price, they can run over $240 each vs a 35ah SLA battery which runs around $65 each.
I lean to carrying in a gas motor myself whenever I have a long distance to travel and I'm running 10amp or more and need a big battery.

Be careful when looking at batteries. You can't simply factor 4hrs of runtime at 14amps for a 56ah battery. These ratings are for a discharge down to 10.5v and the bilge pumps won't be running very strong. You want to give yourself a good 20% margin.


I was just reading up on some of the Li-ion phosphate batteries from a manufacturer (Deltran battery tender) and noticed a major issue. They use a equivalent rating to a SLA battery for choosing the size of a battery but it only relates to engine starting equivalency. It does not look like there 4lb battery with an equivalent rating to a 35ah SLA means it will supply 35ah when running constant current to bilge pump or other load. Looks like this type of misleading marketing is being used by several manufacturers. Sorry for mentioning Li-ion phosphate.

 

[mike(swWash)]

We can't use gas pumps this time of year, only electric and there in lies my dilemma.

I'll be running a 2200gph Johnson @ 7amps plus an 1100gph @ 3.5 amps as an added supply for a 12" sluice with a 3/8" grizzly and will be putting in some slower flow gold hog mats, probably alternating Razorback, Down Draft and trimmed Scrubber running continuous 4-5 hrs. for -50 to -200 flat gold.

 

[Goldwasher]

How about a narrower longer sluice mike. You can get more speed with the volume of water. It will help those matts run better.
When I first was dialing in our sluice for the claim I was using a 12" by 48" sluice...ur..scrubber..bedrock. Using a semi trash pump getting on avg. 40 gpm...at about the same classification as you. It would move material through the box. But, I would get build up of material at the head. And there wasn't enough speed to make the matts fully active. I switched to a ten inch wide box, with more aggressive matts Talon...razorback.. with some downdraft thrown in. It works much better with that amount of flow.
I did quiet a bit of testing with bank run material salted with lead of various character, size weight. clean material that has been washed and ran over and over just doesn't give field accuracy. That narrower box ran waaaaaay better with excellent recovery and beautiful active matts. If I had a 150 gpm I would run the 12" box for recovery. Its now our rough box nugget trap. sending everything to 1/4 classification inputting to the 10"x 48" recovery box. with the matts a mention running at 40 gpm.
I set it to about 7% grade. it recover -100 mesh cold down to smaller than 200. it holds quartz sand with gold attached...wirey stuff flat kitey stuff...its a great fine gold box.

have you looked at the Johnson or rule 300gph pumps? they run 60 to 100 bucks. you would only need to carry one pump to get the same flow.

I realize you probably own your pumps already...here's some pumps though its a good site it give the tech. specs. right on the front page per pump for comparison. Marine Electric Bilge Pumps - Non Automatic on Sale

 

[Timberdoodle]

I was just reading up on some of the Li-ion phosphate batteries from a manufacturer (Deltran battery tender) and noticed a major issue. They use a equivalent rating to a SLA battery for choosing the size of a battery but it only relates to engine starting equivalency. It does not look like there 4lb battery with an equivalent rating to a 35ah SLA means it will supply 35ah when running constant current to bilge pump or other load. Looks like this type of misleading marketing is being used by several manufacturers. Sorry for mentioning Li-ion phosphate.

 

[Capt Nemo]

Might be time to think fluid bed! My model 4.1 runs a Tsunami 800 gph bilge pump at under 3A. It's doing a fine job pulling gold out of beach sands. I'm running this bed as a recirc to avoid any government entanglements.(pump permit)




I'm about to build model 5 which will have a grizzly system. It will probably need a second pump for the grizzly and bring total draw to 6 A.

 

[mike(swWash)]

Yep, already have some pumps. I used to use vortex mat on my 12" sluice but, using 3/16" punchplate the holes get plugged fast with the smaller pea gravel and I started losing gold out the grizzly. That's why I'm going to use hog mats and a larger classifying system. I thought about doing a 9" sluice 4' long. I'll just have to pick up a sheet of abs and bend a new one up when I get the time.

 

[motohed]

I would still look into lithium ion batteries even if you had to haul four or five it would still be less weight , I use them in my high performance motorcycles and they preform better than regular acid batteries hands down . You will also need a charger for them definately the way to go .

 

[KevinInColorado]

Whippet engineering sells some nice lithiums and a smart charger to go with them... Www.Whippetengineering.com

 

[Hamfist]

The LiFePO4 batteries are super light but they are still expensive. The amp-hour rating on some (most) of them is misleading so you really need to look at the watt-hour rating. The K2 Energy batteries that Whippet Engineering sells have a proper, corrected amp-hour rating on them, as do the CTC batteries on Amazon. The biggest I've seen is a 20 Ah CTC and it runs $260. Pretty expensive. You'd still need a solar panel to get much more than an hour of use with pumps drawing 14 amps. You don't want to run lithium so all the way down because it shortens their lifespan.

There's also the Optima yellow D51. It's a 26 lb deep cycle lead acid battery with a 38 Ah rating for about $150. That would run 14 amps for about 2.5 hours without solar charging.

 

[Ragnor]

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