Newbie with questions

[EzPc]

Good day and thank you in advance for your time and assistance.

So I am working my way through Wills book and am in the process of building my first DYI solar system for my detached garage. So far I have already acquired one of the new EG4 3kW Off-Grid Inverter and still need to get a battery and panels. I have been considering one of the EG4-LifePower4 Lithium Batteries as they are made to work with their Inverter and its what I saw Will test in a recent video. However since this is a garage that does not have constant heating and is only heated when being used I was considering one of the Trophy heated batteries. Right now I just want to get started so the plan is a 48v system one inverter, one battery and panels. At some future point maybe a mini split or some other method of heating will be considered. I use a propane heater now when I am in the garage during cold weather. Am I making too much of the heated battery need I live in NJ and we did get some really cold winter days and nights the last couple years here.

 

[rmaddy]

LiFePO₄ batteries must not be charged if the battery is 32ºF or lower. If it can get below freezing inside your garage for a few days, allowing the battery to get down below freezing, then you probably want a heated battery.

 

[EzPc]

LiFePO₄ batteries must not be charged if the battery is 32ºF or lower. If it can get below freezing inside your garage for a few days, allowing the battery to get down below freezing, then you probably want a heated battery.

Thank you for that insight... I have 2 in spayed on foam inside of a steel garage 26 x 25 dimentions with a 9 ft peak... I don't believe it got below freezing this past winter but that does not mean it can't happen. Still unclear if the Trophy battery will communicate with the EG4 inverter like thier battery can. Maybe a couple of RV Water Tank heaters attached to the outside of the battery case can work as a battery heater?

 

[DThames]

If you have an insulated enclosure for the battery, it could retain heat better. You can also put a tiny heater in the enclosure to help, if needed. Will you being using the system every day? Charging and discharging will make a little heat, so if you can retain and monitor the temp in the enclosure, you might be fine.

 

[EzPc]

If you have an insulated enclosure for the battery, it could retain heat better. You can also put a tiny heater in the enclosure to help, if needed. Will you being using the system every day? Charging and discharging will make a little heat, so if you can retain and monitor the temp in the enclosure, you might be fine.

Not everyday and the discharge of the batteries will not be daily no at least to start... I will be working towards that goal, to include in the not to distant future a refrigerator, PC setup with monitors and maybe a couple servers... the direct need is for lighting, the occasional 5 HP air compressor, maybe a 110v mig and/or stick welder and a hydraulic pump for my QuickJack system. With your suggestion it would seem to make more sense to purchase the EG4 battery for communications compatibility out of the box... no?

 

[DThames]

Not everyday and the discharge of the batteries will not be daily no at least to start... I will be working towards that goal, to include in the not to distant future a refrigerator, PC setup with monitors and maybe a couple servers... the direct need is for lighting, the occasional 5 HP air compressor, maybe a 110v mig and/or stick welder and a hydraulic pump for my QuickJack system. With your suggestion it would seem to make more sense to purchase the EG4 battery for communications compatibility out of the box... no?

If the EG4 battery will communicate to the inverter and if the inverter can report temp status via Internet app, that would help you a lot to see if your battery temp situation was under control.

 

[EzPc]

If the EG4 battery will communicate to the inverter and if the inverter can report temp status via Internet app, that would help you a lot to see if your battery temp situation was under control.

The integrated communication of the EG4 battery to inverter was what was making me think twice about using any other battery but the Trophy appears to be one of the only server battery packs that have built in heaters... will take the weekend to decide on which battery and now I have to figure out what panels to get .. and how many... 48v 100AH is what I have to figure for..

 

[Rednecktek]

48v 100AH is what I have to figure for..

Maybe as a starter battery but pretty soon you'll say to yourself "Self, I should get another battery, that fridge/radio/MargaritaMaster-9000 is eating up the capacity pretty fast!" and then you'll want more panels to charge the 2 batteries before you say to yourself "Self, those 2 batteries are great but that Jacuzzi is really eating them up!" and you'll get a 3rd and 4th battery then need more panels to charge them...

I can stop any time I want to, really... It's not a "Problem"...

 

[12VoltInstalls]

take the weekend to decide on which battery

Don’t take battery temp lightly. It’s much more costly to replace a battery than plan properly. An insulated box just delays the inevitable in low temps.

I know I know. 1000 people are going to say they buried in the ground with 2 inches of foam and it’s been fine for 7.3 decades. But ask yourself a question. Do you feel lucky?

 

[Rednecktek]

::Rolls a 1::

 

[EzPc]

Both points are valid... so why not take the next step and consider a battery than can be serviced by the user.... SOKs are the only ones I see are serviceable.... Oh and as for panels was thinking of starting with 14 used from Santan Solar... about 14 240 - 250 W pannels....

 

[DThames]

You do what you think best but if the system is not used daily, you don't need to leave PV connected to the charger. I have an standby system and every morning it wants to go to Boost mode even if there has been no battery drain. I have reduced by "boost reconnect" value to be below the settling voltage so it only will go back to boost if there has been some use. If you have an easy way to monitor the temperature of the batteries, you can monitor for some period and see if you think you really want to worry with a heater or not. You can also build circuitry to disable your PV input under some conditions if your charger doesn't provide that specific protection. So you could add heaters later or just decide to not charge when the battery is cold.

One concern about insulated batteries are them gaining heat when charging/discharging when the weather is warm.