Learning about batteries

[gtinseth]

I just wanted to share my experience building a system for my Vanagon while waiting for a Trillium Outback that didn't happen (another story, not relevant here).

I bought the following:

* 12v 100ah LiFePO4 battery from alibaba (Ctechi brand) - $420
* Epever 3215bn MPPT charge controller - $120
* Progressive Dynamics shore charger PD9130LV - $180
* Sterling DC/DC charger BB1230 - $280
* two 100W pawn shop solar panels - $100

Total cost $1100 USD not counting the connecting bits. So around the cost of one Battleborn 100ah battery or a Jackery 1000 (which has less than 50ah). This system charges all ways at 30 amps with correct programs for this battery chemistry. It is sized to just add another battery or more panels if that is needed. You could add an invertor for not too much if you need AC.

Unlike these youtube and instagram influencers, I don't get free stuff from Battleborn or Victron or Redarc or Jackery and I don't have unlimited money. I am willing to do work myself and that is where this all becomes possible.

Note that Renogy now makes a unit that combines the MPPT and DC/DC charger for around $250 so you could save an additional $150 off my total price. My point is that it doesn't have to cost many thousands of dollars and you don't have to do it all at once.

Edit: I forgot to mention that you could build your own battery ala Will Prowse for half of what I spent on my battery, saving around $200, so $750 total cost if you also use the Renogy unit.

[nofieldfive]

Originally Posted by gtinseth

I just wanted to share my experience building a system for my Vanagon while waiting for a Trillium Outback that didn't happen (another story, not relevant here).

I bought the following:

* 12v 100ah LiFePO4 battery from alibaba (Ctechi brand) - $420
* Epever 3215bn MPPT charge controller - $120
* Progressive Dynamics shore charger PD9130LV - $180
* Sterling DC/DC charger BB1230 - $280
* two 100W pawn shop solar panels - $100

Total cost $1100 USD not counting the connecting bits. So around the cost of one Battleborn 100ah battery or a Jackery 1000 (which has less than 50ah). This system charges all ways at 30 amps with correct programs for this battery chemistry. It is sized to just add another battery or more panels if that is needed. You could add an invertor for not too much if you need AC.

Unlike these youtube and instagram influencers, I don't get free stuff from Battleborn or Victron or Redarc or Jackery and I don't have unlimited money. I am willing to do work myself and that is where this all becomes possible.

Note that Renogy now makes a unit that combines the MPPT and DC/DC charger for around $250 so you could save an additional $150 off my total price. My point is that it doesn't have to cost many thousands of dollars and you don't have to do it all at once.

Edit: I forgot to mention that you could build your own battery ala Will Prowse for half of what I spent on my battery, saving around $200, so $750 total cost if you also use the Renogy unit.

+1
I have been seriously considering doing the same
Will Prowse, Off Grid Garage have some very informative videos
Example of some batteries with 5-year warranties (off grid garage reports receiving warranty replacements without issue)
https://www.alibaba.com/product-deta...12ca4fc7Wn2CTu
https://www.alibaba.com/product-deta...12ca4fc7Wn2CTu
https://www.alibaba.com/product-deta...61c243a5oVgbrZ
https://diysolarforum.com/threads/wh...4-cells.12685/
https://www.mobile-solarpower.com/
On the above page if you go to solar components Will Prowse gives his recommendations on the various components ie:
https://www.mobile-solarpower.com/ra...ge-676969.html
He also did a recent video on DC-DC chargers he recommends the Renogy 20A

[semievolved]

Originally Posted by gtinseth

I just wanted to share my experience building a system for my Vanagon while waiting for a Trillium Outback that didn't happen (another story, not relevant here).

I bought the following:

* 12v 100ah LiFePO4 battery from alibaba (Ctechi brand) - $420
* Epever 3215bn MPPT charge controller - $120
* Progressive Dynamics shore charger PD9130LV - $180
* Sterling DC/DC charger BB1230 - $280
* two 100W pawn shop solar panels - $100

Total cost $1100 USD not counting the connecting bits. So around the cost of one Battleborn 100ah battery or a Jackery 1000 (which has less than 50ah). This system charges all ways at 30 amps with correct programs for this battery chemistry. It is sized to just add another battery or more panels if that is needed. You could add an invertor for not too much if you need AC.

Unlike these youtube and instagram influencers, I don't get free stuff from Battleborn or Victron or Redarc or Jackery and I don't have unlimited money. I am willing to do work myself and that is where this all becomes possible.

Note that Renogy now makes a unit that combines the MPPT and DC/DC charger for around $250 so you could save an additional $150 off my total price. My point is that it doesn't have to cost many thousands of dollars and you don't have to do it all at once.

Edit: I forgot to mention that you could build your own battery ala Will Prowse for half of what I spent on my battery, saving around $200, so $750 total cost if you also use the Renogy unit.

this sounds like a very nice cost effective approach! $450 for a true 100Ah battery (or 90Ah anyway) that will provide many thousands of recharge cycles and not require maintenance sounds like $$ well spent.



In reponse to the next poster who describes Alibaba batteries with 5 year warranties I would recommend caution. Alibaba battery dealers typically require you send the battery back to them for warranty coverage in most cases. Since that shipping is costly, you might find that just keeping a battery that does not live up to specs is the better option and that the warranty is of limited value.

[semievolved]

Originally Posted by nofieldfive

+1
I have been seriously considering doing the same
Will Prowse, Off Grid Garage have some very informative videos
Example of some batteries with 5-year warranties (off grid garage reports receiving warranty replacements without issue)
https://www.alibaba.com/product-deta...12ca4fc7Wn2CTu
https://www.alibaba.com/product-deta...12ca4fc7Wn2CTu
https://www.alibaba.com/product-deta...61c243a5oVgbrZ
https://diysolarforum.com/threads/wh...4-cells.12685/
https://www.mobile-solarpower.com/
On the above page if you go to solar components Will Prowse gives his recommendations on the various components ie:
https://www.mobile-solarpower.com/ra...ge-676969.html
He also did a recent video on DC-DC chargers he recommends the Renogy 20A

FWIW, if you're planning to use individual 3.2V cells and build your own 12V battery, you might want to read the threads on DIYsolarforum about the benefits of constraining individual aluminum clad cells to limit expansion, which can limit life expectancy.

[chrisblessing]

Originally Posted by semievolved

FWIW, if you're planning to use individual 3.2V cells and build your own 12V battery, you might want to read the threads on DIYsolarforum about the benefits of constraining individual aluminum clad cells to limit expansion, which can limit life expectancy.

I built my first 100Ah LiFePo4 per Will Prowse' book and videos. It was a splendid learning opportunity, as well as the chance to power my Scamp for about $600 all in. The DIY solar forum is a never-ending source of information and sources for not only battery and charging technology but for all other aspects of energy generation and conservation.

[Powerwallbattery]

48V Lithium ion Battery use Precautions

1. Lithium-ion battery stored for a long time without use, should be maintained at 50%-60% charge state, should be replenished once every 3 months, and should be charged and discharged once every six months.

2. During transportation, care should be taken to prevent moisture and humidity, and avoid extrusion and collision to avoid damage to the lithium-ion battery.

3. In low temperature, it should not be lower than 0°C. Storage at a temperature of 5°C to 10°C is optimal.

4. Prohibit the use or placement of lithium-ion batteries under high temperature (hot sunlight or very hot car), otherwise it may cause battery overheating, fire or functional failure, shortened life.



5. Prohibit storage in places with strong static electricity and strong magnetic fields, otherwise it is easy to destroy the battery safety protection device, bringing unsafe hidden danger.

6. If the lithium-ion battery emits an odor, heat, discoloration, deformation or any abnormalities that occur during use, storage or charging, immediately remove the battery from the device or charger and discontinue use.

7. In the case of lithium-ion batteries, a monthly power loss of 3% to 5% is possible. Self-discharge is temperature-dependent and will be higher as the temperature rises.

8. Complete discharge is the "squeezing" of a battery until it no longer produces any current. Squeeze out any current. In this case, the voltage will drop to 0 volts. If this state is maintained. A chemical reaction occurs at the electrodes of the battery, rendering it partially or completely unusable.

9. Lithium-ion batteries can be used in the temperature range of 10°C to +55°C. However, charging can only be done at a battery temperature of +5°C to +45°C.

I've put together some notes on lithium batteries, more information is available here: https://www.bsl-battery.com/what-is-...m-battery.html

[gordon2]

This is my Chins brand $ 360 (US), 1280 watt hour LiFePo4 battery in a 40 lb portable box with six fused circuits (two are connected) and a master switch (breaker). The add-ons are things I had on hand… cheaper options would be fine. Current price on the battery is $380 but it will go back down. Will Prowse opened one up and found the quality to be good with the only real strike against it the lack of low temp cutoff on the BMS.

This box goes where the power is needed. It’s easy to lug around 40 lbs. I can run ham radio gear off it, power my portable fridge, run a tire inflater, and best of all connect it to the system in my camper when the primary AGM battery is depleted to give me an extra 80 or 90 amp hours. The camper hook-up takes all of 30 seconds the way I arranged it.

I keep it about half charged and only fully charge it when use is expected. For that reason it should keep most of its capacity for ten years or more (by which time I expect newer technology to replace it). So that is $36 a year for a long list of optional uses. There is no acid, no corrosion, no need to top it off every month. It just sits there until I want to use it. But if you wanted to charge it 90% all the time I would still expect five year or so of neax full capacity.

I did invest in new charger and can fully charge the battery from empty in about four hours (at 25 amps) which is good if charging from a generator. Or I can set it to 10 amp charge if not in a hurry (using shore power). The same charger works for all my 12 volt batteries also.

On the other hand I could save a few dollars, have a battery with more maintenance and mess but less capacity, and leave the extra few dollars in my will. But neither the battery nor my money follow me when I leave this world.

[jwcolby123]

Originally Posted by Powerwallbattery

48V Lithium ion Battery use Precautions

1. Lithium-ion battery stored for a long time without use, should be maintained at 50%-60% charge state, should be replenished once every 3 months, and should be charged and discharged once every six months.

2. During transportation, care should be taken to prevent moisture and humidity, and avoid extrusion and collision to avoid damage to the lithium-ion battery.

3. In low temperature, it should not be lower than 0°C. Storage at a temperature of 5°C to 10°C is optimal.

4. Prohibit the use or placement of lithium-ion batteries under high temperature (hot sunlight or very hot car), otherwise it may cause battery overheating, fire or functional failure, shortened life.



5. Prohibit storage in places with strong static electricity and strong magnetic fields, otherwise it is easy to destroy the battery safety protection device, bringing unsafe hidden danger.

6. If the lithium-ion battery emits an odor, heat, discoloration, deformation or any abnormalities that occur during use, storage or charging, immediately remove the battery from the device or charger and discontinue use.

7. In the case of lithium-ion batteries, a monthly power loss of 3% to 5% is possible. Self-discharge is temperature-dependent and will be higher as the temperature rises.

8. Complete discharge is the "squeezing" of a battery until it no longer produces any current. Squeeze out any current. In this case, the voltage will drop to 0 volts. If this state is maintained. A chemical reaction occurs at the electrodes of the battery, rendering it partially or completely unusable.

9. Lithium-ion batteries can be used in the temperature range of 10°C to +55°C. However, charging can only be done at a battery temperature of +5°C to +45°C.

I've put together some notes on lithium batteries, more information is available here: https://www.bsl-battery.com/what-is-...m-battery.html

In general this discussion is about LiFePO4, not Lithium Ion. Different chemistry, different behaviors, different problems. Pretty much just different!

[CaptCrunch]

Glenn: Thanks for the thread and all the Will Prowse related links. I like your Battle Born alternative setup.

Gordon: What charger did you go with and do you simultaneously charge the house AGM and the aux. LifePo or is the charger exclusively for the aux. battery?

[gordon2]

Originally Posted by CaptCrunch

Gordon: What charger did you go with and do you simultaneously charge the house AGM and the aux. LifePo or is the charger exclusively for the aux. battery?

Simple question.. but no simple answer.
Victron Blue Smart IP67 12/25 (PN BPC122547106) is not permanently installed.

The battery can be quickly plugged into the camper's electrical system and the primary battery on the tongue shut off (by a switch). In that case the original converter will charge the LifePO4 but not to 100%. As discussed, I am OK with around 95% of full charge and that would help the LifePO4 live longer (even though it should live for many years anyway). But in that case I should disable the "Charge Wizard" because of its desuf mode, and turn off the converter or unplug the LifePO4 when it reaches about 95% of charge. Replacing the converter i an option also.

Or I can use the Victron to charge it when not in the camper. The Victron charges other 12 volt batteries also with different profiles, which is why I keep it portable.

I had considered going exclusive LifePO4 but I would not want that expensive battery on the tongue where it would be easy to find and steal. But removing the 68 lb battery on the tongue and having the 34 lb LifePO4 inside leaves my tongue weight way too low. I could add a second propane tank but if I had two tanks and they were empty, I would again have an unstable rig.

The LifePO4 work well with my radio gear or for my portable fridge. Its light weight and easy to move around. So I think I will stick with this arrangement.

[CaptCrunch]

Thanks for the explanation Gordon…I figured it might be something like that. I’m very intrigued by your set up’s versatility and will likely copy it but I have a couple more questions. Could you please provide some details about where and how you connect the LiFePo4 into your system and do you have any plans to incorporate solar in the future?

[gordon2]

Originally Posted by CaptCrunch

..Could you please provide some details about where and how you connect the LiFePo4 into your system and do you have any plans to incorporate solar in the future?

Of course solar is included ... and a Trimetric battery monitor. Overkill maybe but its my hobby.

Basically there is a the primary battery that goes to a switch which disconnects the battery from everything. After the switch there is a shunt to measure all current going in or out of the primary battery. Everything else on both the load and charging side is after the shunt. Solar controller is in parallel with the converter. There is an Anderson powerpole outlet (rated at 30 amps) which is live when the converter is on or the battery switch is on. This is the original setup for one battery.

The 30 amp powerpole can be "back-fed" so that I can use a separate charger (using the outlet as an inlet if you will), or another battery can be connected there.

But this is not the best practice for a two battery setup and it was not intended to be used that way. For one thing, the shunt only measures current to and from the primary battery. Instead, a three way switch should be used to select either A or B battery, or disconnect both. And then there is the issue of the converter being the type for one chemistry but not the other. So I could rewire it for a proper two-battery setup but except for the weight distribution problem I would prefer to just switch over to a LifePO4 only setup.