On 7/21/2019 at 2:43 AM, Al F said:

Speaking of gambling.  A charge voltage of 14.6V  (3.65V per cell) is at the very top end of the acceptable charge voltage for LFP chemistry batteries. 

https://batteryuniversity.com/index.php/learn/article/bu_216_summary_table_of_lithium_based_batteries

Everything I have seen about lithium batteries state for best life you should avoid charging to 100%.  93% to 95% is best.  

Even the Lithium solar controller you referenced seems to be set for a charge voltage of 14.2V  

I know this get confusing as different sellers of lithium batteries state different things.  Just as in the battery you bought, the seller states the charge voltage to be 14.6V.   That is correct that the battery CAN be charged to that level.  Now SHOULD the LFP battery be charged to 14.6V (3.65V per cell).  You will have to decide that for yourself.  NOTE: I wrote "seller" and not "manufacturer".  A seller can tell you anything they want in order to sell you something.  A mfg will usually, or should, provide detailed info for proper use of a product. 

Above I gave a link to info at Battery University.   Poke around in that website and read the various pages about lithium and charging/discharging/higher temperature affect on battery life, etc.  

I find Battery University's website to be somewhat confusing, but IMO the info and advice is spot on for how to care for the batteries for long life. 

Keep in mind that LiFePO4 chemistry is the same no matter who mfg the battery.  Just as lead acid is the same no matter who make it.  That is all lead acid must be brought to 100% charge frequently or it looses capacity and there have been plenty of charts showing 50% loss in the number of life cycles if you discharge to 50% instead of only discharging 25% (75% full).   Lithium life cycles and safe usage is the same no matter who makes it. 

There is a bit more to it than I thought.  Okay so I will make sure to charge it only to 14.2V, not it's full capacity.

I'll take a look through that site to get a bit more of an education on lith batts.  The last thing I need is to have my van catch fire because I did something wrong with the battery.

On 7/21/2019 at 11:53 PM, Tom_M said:

It's difficult even with the correct tool to get a good crimp on the typical MC4 pin. I would suggest crimping the pin to the wire as best you can, then solder it.

Alright thanks.  I'm not familiar with soldering but this is probably what I'm going to have to end up doing.

8 hours ago, DesertMiner said:

Check these out... 

https://www.victronenergy.com/solar-charge-controllers

Thanks, I'm just taking a look now.

I  have just ordered a very pricey LiFePO4 battery to go with my 160 watt solar panel.  Now I want a MPPT controller and I was hoping someone here could confirm this is the correct controller for the battery and panel.  I believe it is the correct controller but I would like a second opinion please.


The charge controller:


https://fazcorp.co.nz/collections/mppt-s...v-ml2430-1

With a MPPT Bluetooth Communication Module so I can monitor the solar system from my Amazon Kindle:

https://fazcorp.co.nz/collections/mppt-s...ies-bt-1-1

Solar panel:
Standard power: 160 Watts
Maximum power voltage: 17.8
Maximum power current: 9.0A
Open Circuit voltage: 21.1V
Short Circuit current: 9.5A

LiFePO4 battery:
Nominal voltage: 12v
Capacity: 100Ah
Discharge cut-off voltage: 8.4v
Operating voltage min 11.5 V - max 14.8 V At 80 % DOD
Optimal discharge current < 50 A
Charge voltage: 14.6v

3 hours ago, Al F said:

Check the charge parameters for the battery you want to buy.  It should be: to have a charge voltage no higher than 14.2-14.4V and a float voltage of about 13.4-13.6V.    Unless they want to sell you a charger as well as selling the battery.  Of course if they are going to void their warranty if you don't buy their charger, you might want to find a different place to buy the battery. 

 BTW, it matters little what LiFePO4 battery you buy.  They all should have the above general charge voltage parameters.   Also be sure to have the equalize function turned off or set for no higher that 14.2-14.4V. 

Now if your PWM controller is not programmable to the voltage I gave above you should not use it for lithium.

A solar controller for lead acid should be default to 14.6V absorb charging and about 13.4-13.4 float. If you can't change that voltage it is not compatible with lithium. 

The battery I purchased has a charge voltage of 14.6

I think I'll look into buying a charge controller that is definitely for a LiFePO4 battery,  The PWM controller I currently own does have a lithium option but it doesn't specify LiFePO4.  So I'd have to gamble on it being compatible with LiFePO4 batteries, and I'm not willing to gamble.

13 hours ago, hemsteadc said:

No.  I've mistakenly run mine down to almost 0% SOC and it recovered just fine.  As of this writing, you're not supposed to charge them in freezing temps, but the BMS should disallow that anyway.  I'm running my air con with one right now!

You'll love it.  No watering, no corrosion,  no gassing, no hydrometers,  no 50% restrictions, light, and maybe never have to replace it.

Man that sounds good:)

3 hours ago, Al F said:

Also at Battle Born they have a FAQ page:  https://battlebornbatteries.com/faq/  that should have some answers to your questions about lithium batteries.

Yes, there are some restrictions and warnings about using lithium.  

The Battle Born and most others have a build in BMS (Battery Management System) to cut off the batteries from your RV system if you try to over charge them or over discharge them, or charge then when the temperature "inside" the battery is below freezing.  Note, the freezing temps are not what the temperature is out side your RV, but what the temperature is internally in the battery.  You can use them to power your RV (i.e. discharge the battery) down to below zero degrees.  

The chemistry in the lithium batteries we use in RV's is very safe, especially when paired with the BMS.  This is unlike the lithium batteries which were in the Boeing airplane that was in the news a couple of years ago and the batteries in some consumer products that have caught fire. 

One BIG caution.  You really should have a battery charger and solar controller which are programmable so you can adjust the charging voltage to what Battle Born recommends.  I think that is to not supply a charging voltage above about 14.3 volts to 14.4 volts.   Many chargers/controllers will supply 14.6-14.8V which is exactly what lead acid batteries require.  

Here is a link to Battle Born's website about charging parameters:  https://battlebornbatteries.com/charging-parameters-chargers-recommend/

 

 

Thanks for the links, I'm going to have a good read up after work.

4 hours ago, Al F said:

As an Escapee member you can buy the lithium batteries from a company in the USA, rather than New Zealand.  Should be lower shipping costs as well as lower price. 

 

It is actually more expensive.  The battery I plan to buy costs $949NZD ($640USD). 

Shipping a lithium battery within NZ only costs $4USD and shipping lithium batteries internationally is not allowed anyway unless the battery is already installed in the equipment it operates.  

2 hours ago, Al F said:

Gimmy Tree, 

Would you share with us what RV you have, you RV'ing experience, and what your travel plans are.  Will you be doing a lot of dry camping/boondocking, or will you spend quite a bit of your time with electrical hookups?   There is a great deal of difference in battery usage/charging and general requirements between dry camping for 2-3 days once a month or once a week and then back to shore power, than there is if you are planning on dry camping for 5-7 days or more before getting back to shore power.  

Will you have an inverter to power a microwave/coffee maker/toaster, or a satellite TV receiver, or are you just looking to power your lights, cell phones, laptop computer and limited use of your RV propane heater (the fan uses a lot of battery power if it runs a lot at night). 

I don't own a RV, I own a 1999 high roof Toyota Hiace which I plan to live out of full time.  It's still in the conversion stage and because I can only work on it one day per week, I've got a two more weeks before it's finished.

I do plan on doing some traveling (I'm located in NZ) but generally I'll be staying in the same town because I have a full time job.  The traveling will be done on weekends and holiday's.

I'll be mostly boondocking near a beach where I previously lived for nine years, so I know the area well.

I have a pure sine wave inverter and I'll be powering a laptop, 2 x kontiki batteries (by plugging the kontiki charger into the inverter), a mobile and a kindle.  A kontiki is a fishing device, if you're not familiar with it.

2 hours ago, Al F said:

Gimmy Tree,

You are asking great questions and receiving many good answers.  I believe you are pretty new to all this RV electrical stuff, like batteries, solar, battery charging, how much power each of the devices in your RV uses, etc.

Here are some excellent links to detailed info that should give you more concise and detailed info, than the short answers you receive from forum topics. 

Very good basic info in this 2 part website.  Be sure go to part 2 at the bottom of part 1's website.  "The 12V side of life"

Here is a rather technical website that has very good detailed info for designing and operating RV electrical systems:  http://www.jackdanmayer.com/rv_electrical_and_solar.htm

This website pretty well lays out the entire RV electrical system from shore power to solar power:  https://www.rv-dreams.com/rv-electrical.html

Here is a link to a article about what to look for in a quality install and especially what not to do.  The writer has very strong opinions and is rather blunt, as well as over wordy, but the advice is pretty much spot on.  http://handybobsolar.wordpress.com/the-rv-battery-charging-puzzle-2/

It's currently 5am and I have work in a couple of hours but I'll have a good read of those sites when I get home.  Thanks for the links:) 

I was just about to buy the battery below for my 160 watt solar panel but there is a lot of different guidelines and warnings on the battery:

https://www.trademe.co.nz/motors/caravan...ed0d07-003

My questions are; Are Lithium Iron Phosphate batteries easily damaged compared to lead acid batteries?

Is a newbie like myself better off with a lead acid battery?

6 hours ago, Chad Heiser said:

See above for answers in red.

Ah good answers, that explains things.  I'll have to watch a few YouTube video's on how to crimp MC4 connectors without a crimper.

This one: https://www.trademe.co.nz/business-farmi...b7393b-001

Or this one: https://www.trademe.co.nz/motors/caravan...1883d5-001

I know the lithium iron phosphate batteries are better than the lead acid batteries, so I assume all lithium iron phosphate batteries are deep cycle batteries?, is my assumption correct?

My solar panel is 160 watts and I currently have a PWM solar charge controller (30V) which apparently aren't very efficient and loss 30% of solar power.  So a MPPT solar charge controller was recommended.  My question is; will this controller be okay for a 160 watt solar panel, or should I buy one of the smaller ones?

https://www.amazon.com/dp/B07429RK43/ref=as_li_ss_tl?psc=1&pd_rd_i=B07429RK43&pd_rd_wg=2Tk2y&pd_rd_r=92XADJVX85X17T90PT7F&pd_rd_w=R7yk9&linkCode=sl1&tag=vehicledwelling-20&linkId=8b93017dcab6009786a3f874e2280e87

18 hours ago, Kirk W said:

Welcome to the Escapee forums!

I am no soloar power expert, but I do have a lot of electrical work experience. Here are some basic instructions that may help.

Solar Panel Charge Controller Wiring Diagram & Steps

In addition, you may find it very helpful to visit Youtube and watch some of the videos available there. 

Thanks for the information.  Much appreciated:)

Here is the solar charge controller with the wires and connectors that came with the kit: https://ibb.co/xLM72kS

This is the pure sine wave inverter with wires and connectors: https://ibb.co/VQJT3Sz

And the solar panel wire connectors: https://ibb.co/Qbb1CrW

I have one pair of mc4 solar panel connectors on order so I can connect the solar panel to the wires.
I assume the white wire (which is quite long and has positive and negative wires in it) connects to the solar panel and the solar controller, correct?

Do I need to buy positive and negative wires to run from the battery to the controller?  The solar kit I got doesn't seem to have those wires.
The kit was suppose to have come ready to set up, does it look like I have everything to setup the solar panel kit?  (battery is still to come)