Portable battery recommendations

[fremont]

Did a search but didn't find an exact match regarding what are the characteristics of a good portable battery.  I like that this one has Powerpoles already attached and is lighter.  Thinking of using my TK-880 in outdoor applications where there's no power other than my truck.

[marcspaz]

25-35 ah battery will give you hours of 50w use.  If you go 5w or 15w, you can use a smaller 10-15 ah battery and still run for several hours.  I have a 100 ah SLA AGP battery that I can run a 100w radio for 11-12 hours at 50% duty cycle.  My battery weighs almost 70lbs, so unless you need it, I wouldn't go that large at all.

[Elkhunter521]

Hi Marc, what type of battery

[Lscott]

Did a search but didn't find an exact match regarding what are the characteristics of a good portable battery.  I like that this one has Powerpoles already attached and is lighter.  Thinking of using my TK-880 in outdoor applications where there's no power other than my truck.

Try looking at battery packs from this company. They do a lot of business with Hams for portable operations. They have pretty good prices considering.

 

https://www.bioennopower.com/collections/12v-series-lifepo4-batteries

 

Personally I have the 6AH pack ($80) for portable work with HT's. I have the 40AH ($360) for home use when the power dies. If you get the batteries make sure to buy the charger too. The 6AH LFP weights a lot less than the old 5AH Lead Acid Gell Cell, and with much more usable capacity too.

 

I don't recommend anybody use a Lead Acid battery unless cost is an extreme concern. Personally I've wreck too many Gell Cell and AGM batteries to want to fool around with them anymore. If you don't maintain them at full charge when not in use they will sulfate and fail. And if you do they still don't last that long.

 

The other disadvantage is the terminal voltage falls fairly quickly to the point where you're lucky to get maybe 50 some percent of the rated capacity out of them. Most mobile equipment wants to see a nominal 13.8 VDC (+/- 15 %) and when it drops to around 11.75 VDC the equipment misbehaves or shuts down. Then there is the weight.

 

Using LFP, Lithium Iron Phosphate (LiFePO4), batteries have a nominal terminal voltage of around 13.3/13.4 VDC over most of the full discharge range, which is a good match for mobile equipment. By the time they drop to 12.8 VDC you have used around 90 percent of the rated capacity. The batteries will routinely allow you to discharge them to 80 to 90 percent without damage. Under this kind of use expect to get around 2000 charge/discharge cycles out of the pack. Lead Acid is only good for a few hundred when using just 50 percent, using more the cycle life drops even more.

 

You can charge up a LFP battery and let it sit for weeks to months without it hardly self discharging. Further for very long term storage you only partially charge them. Sitting around for very long periods doesn't seem to hurt the batteries at all. 

[marcspaz]

Hi Marc, what type of battery

Duracell. I'll share a picture tonight.

[marcspaz]

Try looking at battery packs from this company. They do a lot of business with Hams for portable operations. They have pretty good prices considering.

 

https://www.bioennopower.com/collections/12v-series-lifepo4-batteries

 

Personally I have the 6AH pack ($80) for portable work with HT's. I have the 40AH ($360) for home use when the power dies. If you get the batteries make sure to buy the charger too. The 6AH LFP weights a lot less than the old 5AH Lead Acid Gell Cell, and with much more usable capacity too.

 

I don't recommend anybody use a Lead Acid battery unless cost is an extreme concern. Personally I've wreck too many Gell Cell and AGM batteries to want to fool around with them anymore. If you don't maintain them at full charge when not in use they will sulfate and fail. And if you do they still don't last that long.

 

The other disadvantage is the terminal voltage falls fairly quickly to the point where you're lucky to get maybe 50 some percent of the rated capacity out of them. Most mobile equipment wants to see a nominal 13.8 VDC (+/- 15 %) and when it drops to around 11.75 VDC the equipment misbehaves or shuts down. Then there is the weight.

 

Using LFP, Lithium Iron Phosphate (LiFePO4), batteries have a nominal terminal voltage of around 13.3/13.4 VDC over most of the full discharge range, which is a good match for mobile equipment. By the time they drop to 12.8 VDC you have used around 90 percent of the rated capacity. The batteries will routinely allow you to discharge them to 80 to 90 percent without damage. Under this kind of use expect to get around 2000 charge/discharge cycles out of the pack. Lead Acid is only good for a few hundred when using just 50 percent, using more the cycle life drops even more.

 

You can charge up a LFP battery and let it sit for weeks to months without it hardly self discharging. Further for very long term storage you only partially charge them. Sitting around for very long periods doesn't seem to hurt the batteries at all.

 

This is great advice. I would love to get an LFP and it may be next battery. My system primarily runs off of the solar panels and the battery is there to handle heavy draw spikes when I need to use the amp. I think I need a different solar system to switch to LFP.

[TomWRHZ479]

Another source you may want to consider is Dakota Lithium (https://dakotalithium.com)

 

I have one of their 10Ah batteries and use it often to power multiple devices. It's about the size of 4 packs of cigarettes and weighs under 3 pounds.

[marcspaz]

Another source you may want to consider is Dakota Lithium (https://dakotalithium.com)

 

I have one of their 10Ah batteries and use it often to power multiple devices. It's about the size of 4 packs of cigarettes and weighs under 3 pounds.

 

 

I just checked them out.. wow, their warranty is great. 11 years on the 100 ah deep cycle. But its almost $1,000. I may go this route if the solar system I have will charge it... but I'll be crying the whole time. LoL

[Lscott]

This is great advice. I would love to get an LFP and it may be next battery. My system primarily runs off of the solar panels and the battery is there to handle heavy draw spikes when I need to use the amp. I think I need a different solar system to switch to LFP.

You likely can use the panels you have now. However you do need a charge controller specific for LFP batteries. I got a couple of the 5 amp ones from the company below, Genasun. They’re good for up to maybe a 50 watt panel more or less. I think you can parallel the controllers. These are the good MPPT, max power point tracking, type, not the crappy PWM ones you typically find on many systems.

 

https://sunforgellc.com/

[marcspaz]

You likely can use the panels you have now. However you do need a charge controller specific for LFP batteries. I got a couple of the 5 amp ones from the company below, Genasun. They’re good for up to maybe a 50 watt panel more or less. I think you can parallel the controllers. These are the good MPPT, max power point tracking, type, not the crappy PWM ones you typically find on many systems.

 

https://sunforgellc.com/

 

Fantastic.  I appreciate the lead.  I will check them out.

[GuySagi]

I interviewed some of the big wigs at Battle Born batteries for a story a while back. The company also makes/sells LFP chemistry batteries, but specializes in versions for RVs and trailers. Aside from that long as heck warranty the firms can offer and lighter weight there are a couple other things that really caught my attention. Batteries that use this technology take a charge much faster (especially in the initial phase of that cycle, decreasing generator or solar time for people boondocking). Most traditional battery recharging controllers can't take advantage of that, though, hence the nearly universal recommendation for a new one (there are other charge-rate/cycle concerns, too). Off gassing eliminated or gone, allegedly leak proof, which allows the batteries to be stored in virtually any configuration or place (sideways, in a closet...). Compared to traditional cells more usable energy (not amp hours or watts, but the ability to deliver them as voltage drops into the ranges traditional cells quit working and begin to suffer damage).  There is one downside, according to what I was told. Temperature. When the thermometer dips too low they get really bad at taking a charge and sharing energy....hence this company recommends installing them in the cab of an RV (not outside) and removing if you're storing your rig for the winter. Don't quote me on this, but I think that was right at or just below 32 degrees. Cells for RVs are also just a bit larger than traditional ones (not much, but worth measuring battery boxes when you order).

 

I'd tell you I love mine, but budget has prevented me from buying one of the $1K batteries...at this point, anyway. It's definitely on my list, but I'd be a jerk if I didn't footnote the fact I'm relaying the company's side of the story, not personal experience. Hope everyone and their loved ones have a glorious and healthy day. 

[Lscott]

These guys have solar panels, charge controllers and some batteries too. I got a couple of their 50 watt, one 30 watt and four 10 watt mono-crystalline panels. Prices are OK for new.

 

https://www.renogy.com

 

Example of a nice portable 30 watt panel. Not that large. The 50 watt panels are good but not as easy to carry around. Some people get a couple of panels then bolt them together using a door hinge, with cabinet drawer loop handles on the end, so they can be folded up for easy transport.

 

https://www.renogy.com/30-watt-12-volt-monocrystalline-solar-panel-new-edition/#prd-specs

 

If you're lucky you can find used panels at swap meets. Most of the time people seem to want around $1/watt or more, which is a bit much for used panels. What you quickly notice as the panel power goes up the cost per watt drops, for new panels.

 

If there is no rating for the panel a simple measurement with a meter will give you an idea of approximately how much power you can expect to get out of one. Yeah, I'm one of those guys who at times takes a meter to swap meets.

 

1. In full direct sun light measure the open circuit voltage of the panel.

2. In full direct sun light measure the short circuit current out of the panel. This will vary depending if the panel is at exactly pointed at the sun or off a bit.

3. Multiply the above two readings then multiply by 0.75 (which is the typical "fill factor" its called, to get the "STC" panel rating. Under typical operating conditions don't expect to get much more than around 75% of the above rating.

 

For the example panel above you get:

 

Voc= 22.9 VDC

Isc= 1.7 Amps

 

Panel Rating = 22.9 * 1.7 * 0.75

Panel Rating = 29.2 Watts (Manufacture lists at 30 Watts)

 

Real Max Output Power Expected = 30 * 0.75

Real Max Output Power Expected = 22.5 Watts

 

You can get the Anderson Power Pole connectors at this site, crimping tool as well. I got the big set because I wanted to make a bunch of patch cables.

 

https://powerwerx.com/anderson-power-powerpole-sb-connectors

 

Another handy tool is an in-line DC power meter from them. You can keep track of how much power you're producing out of the panels and the amp hours you use from the battery. I got two of these as well, one for the solar panel array and the other for the battery pack.

 

https://powerwerx.com/watt-meter-analyzer-inline-dc-powerpole

 

For long cable runs forget the expensive red and black zip cord cable, costs too much. I went to Home Depot, or Lowes, and got a big roll of 12 gauge stranded low voltage direct burial lighting wire, black zip cord type. Then just stick the power poles on the ends after making sure you got the polarity right. With the red and black power poles on the ends who cares what the wire colors are?

 

https://harriscountyares.org/training/KNW/KNW-120.pdf

 

You want to use the heavy gauge wire because at low voltage and high current the voltage drop can be significant. The large gauge wire gauge keeps the voltage drop way down even on lower power systems.

[marcspaz]

Hi Marc, what type of battery

 

 

Duracell. I'll share a picture tonight.

 

 

I forgot to post these after I took the picture.  Keep in mind, for the sake of this topic... this is not very portable @ 67lbs. 

 

 

 

http://fiveguysracing.com/marc/HAM-GMRS/20200723_190831.jpg

 

 

http://fiveguysracing.com/marc/HAM-GMRS/20200723_190844.jpg

[GuySagi]

Just FYI. One of the rv newsletters I subscribe to ran this article on batteries today

 

https://camperreport.com/rv-lithium-batteries/

[Lscott]

Just FYI. One of the rv newsletters I subscribe to ran this article on batteries today

 

https://camperreport.com/rv-lithium-batteries/

Nice article. One needs to understand there are several different Lithium battery chemistries which was not made clear.  Some are a bit dangerous and can become unstable under certain conditions. The worse is Lithium-Ion. Lithium-Ion has one of the highest energy densities and why its used in EV battery packs. The protection and monitoring systems built into them is extensive. The other chemistry is Lithium-Polymer which sees use in flying drones where you need the most power and energy storage with the least weight. Those people have to be careful as there have been fires from battery failures.

 

The reason why Lithium Iron Phosphate is the recommended chemistry is due to it's very high stability. The down side is the energy density, watt-hours per unit volume or watt-hours per unit weight, is  a bit lower than for the other types but still much higher than for Lead Acid batteries. Over all for portable use its a good trade off.

[GuySagi]

Great points. Thank you.

[Woodcat]

Have to wonder if this compact and powerful battery pack would suit your needs.  Affordable lithium.

https://www.amazon.com/dp/B015TKUPIC/?coliid=ISW57JMHU7YJ5&colid=1CWQPPPTXZ2VP&psc=1&ref_=lv_ov_lig_dp_it

Craig