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Battery talk (A place to discuss any and all battery technologies where the discussion may not fit into other topic areas) => Other => Topic started by: jlowens76 on May 05, 2022, 08:19:38 PM

Title: What chemistry
Post by: jlowens76 on May 05, 2022, 08:19:38 PM
Getting started with an inverter/battery setup to run about 1100 watts, for as long as I can (USP type setup for now, would like to expand with solar and possible grid tie later)

Main question is, which type of battery should I go with... Been looking at LiFePO4 but obviously that is the more expensive option

Is that the best, vs SLA or something like the EnergyCell 200RE Deep cycle AGM?

Title: Re: What chemistry
Post by: mike90045 on May 06, 2022, 02:02:14 PM
Best for getting your feet wet, and least cost on the wallet, would be marine deep cycle batteries 12V 100ah.
As for how many you need, do you know your daily loads in watt-hours ?

If you need more storage, 6V 200ah golf cart batteries are a low price point too.   Many folks inadvertently ruin their first set of batteries, mostly from undercharge or overly discharging them.   

A 1kw inverter is about the limit of what a 12V system can safely drive, the amps at the DC voltage get very high, very quickly.
It's better to string batteries into a 24V system, than to parallel the same batteries into a 12V system.

1000W of load :
12V  84A
24V  42A
48V  21A
120V  8.3A
   It's much easier and less expensive to route 0 gauge cable for 48V, then to wrestle 000 cable

Title: Re: What chemistry
Post by: jlowens76 on May 08, 2022, 05:28:51 AM
Quote from: mike90045 on May 06, 2022, 02:02:14 PM
Best for getting your feet wet, and least cost on the wallet, would be marine deep cycle batteries 12V 100ah.
As for how many you need, do you know your daily loads in watt-hours ?

If you need more storage, 6V 200ah golf cart batteries are a low price point too.   Many folks inadvertently ruin their first set of batteries, mostly from undercharge or overly discharging them.   

A 1kw inverter is about the limit of what a 12V system can safely drive, the amps at the DC voltage get very high, very quickly.
It's better to string batteries into a 24V system, than to parallel the same batteries into a 12V system.

1000W of load :
12V  84A
24V  42A
48V  21A
120V  8.3A
   It's much easier and less expensive to route 0 gauge cable for 48V, then to wrestle 000 cable

Thanks for the reply! Although somewhat new, that's really only in the concept of actually owning/having my own equipment. I am familiar with most of the topics, electricity in general, inverter battery voltage/amperage payoff of higher voltage = lower amperage = smaller cables = less money.. I am just really not familiar with what most people use/and or what is the best battery chemistry used in todays setups.

While I am looking to get started, I am not exactly looking to dip my toes so to speak as I don't want to waste money on something I will just need to upgrade.

While my whole house power consumption is WAY more(about 99kW/day according to screenshot attached) than anyone could think to try to substitute via battery/solar, I am going for more of a UPS backup approach to basically power a few circuits if the power goes out. So with that in mind I am looking to get maybe a 3kw+ inverter, and batteries to get me started(adding battery capacity later)

I am looking at the EG4 LifePower4 Lithium 48v 100AH,  as its a strikingly nice all in one solution and modular(rack mount) $292/kWh.. Seems like a pretty good price point for LiFePo4 batteries.

I would NEVER generate enough power to ever "sell back" but would eventually like to expand via solar panels and maybe offset some of the energy consumed, to reduce my bill.

I am also wondering if the Midnite DIY inverter would be a good option for this type of "UPS style" configuration.