Lithium battery

[DanK]

Is there any advantage or disadvantage to using a single 200 amp hour lithium battery over 2 - 100 amp hour batteries. I realize the single is going to be bigger size wise, but the weight would be about what a single lead acid weighs

[Centex]

IMO, when considering a single LiFePO4 battery with internal BMS of Ah rating "X" vs multiple LiFePO4 batteries with internal BMS in parallel yielding a total aggregate Ah rating "X" (note none of this is in comparison to any other battery option, just between the LiFePO4 packaging options for a given Ah rating "X") ...

Pro

• simplified wiring
• eliminate any concerns about balancing between batteries
• usually somewhat less total footprint area / battery bank volume
• sometimes somewhat lower total battery bank weight

Con

• higher weight of the individual battery for purposes of handling

Caveats

• the net input/output characteristics of the battery bank may not be directly comparable depending on the internal BMS specifics of the batteries in question (e.g. continuous and surge-per-unit-of-time rates of discharge; recommended rates of charge, etc); this may or may not be an issue depending on your objectives / anticipated use-habit, probably not an issue when the objective is long-duration support of moderate amp loads as opposed to support of very high peak amp loads.
• the shape / dimensions of the battery bank footprint my be more or less amenable to a given installation space
• when comparing cost, consider not only the $/Ah of the battery bank but also the cost of required interconnects for each option

Not an exhaustive or all-inclusive list, but factors that came to me and affected my decision when considering the 'single big vs multiple small' LiFePO4 options for myself (FWIW I settled on a 'single big' solution, but YMMV for any number of good reasons).

Just for Your consideration, Have Fun!

[alanmalk]

Originally Posted by DanK

Is there any advantage or disadvantage to using a single 200 amp hour lithium battery over 2 - 100 amp hour batteries. I realize the single is going to be bigger size wise, but the weight would be about what a single lead acid weighs

I chose a pair of 100 Ah batteries for two reasons: Ease of lifting for winter storage (one of my prime reasons for buying Lithium in the first place), and second, each battery is rated for 100 amps of continuous discharge (useful for inverters). Another reason to consider: You may want 300 Ah total rather than 200, easy to achieve with 100s.

As mentioned earlier: Be aware that any given 200 Ah, or even 300 Ah batteries may have a limit of 100 amps of continuous discharge, which restricts use of large inverters. I have seen this limit on many of the cheaper no-name batteries that have appeared on the market recently.

[splitting_lanes]

I emailed Escape about a 200AH battery, and it was physically too large.

There are some 125-150 AH batteries that should fit, and some can discharge more than 100amps.

[DanK]

Let's say the largest power draw item I plan on ever using is a microwave hooked up to a 2000 watt inverter , do I need more then a hundred amps of continuous discharge . Sorry electric is not one of my strong points

[alanmalk]

With a very small microwave you might get by with 100 amps continuous draw. But in a realistic situation you really should have a battery supply that can provide 200 amps to your 2000 watt inverter. Conversion from DC to 120 VAC is rarely more than 90% efficient. Meaning, some of your amps are going directly into the air as heat, not into the microwave.


Big bursts of amperage is one of the strong points of a pair of 6 volt lead-acid batteries.

[Centex]

Dan, can you provide the make/model for whatever ~200Ah LiFePO4 battery / batteries have caught your eye? Even better, a link to the webpage or specs?

Originally Posted by splitting_lanes

I emailed Escape about a 200AH battery, and it was physically too large.

There are some 125-150 AH batteries that should fit, and some can discharge more than 100amps.

Did ETI say exactly why "too large"? One factor to remember is that, for reasons that we don't need to rehash here, ETI insists on installing even LiFePO4 batteries in a sealed box vented to the exterior. It's possible that their "too large" relates to the sealed-boxes they are willing to source, unrelated to overall space under a bench.

Are you willing to consider post-delivery DIY solutions or only solutions that ETI will implement (sorry, not sure if the E21c in your profile is in your hands now or yet to-be-delivered, or maybe these questions in the context of a different trailer)?

[Jack!]

Originally Posted by Centex

It's possible that their "too large" relates to the sealed-boxes they are willing to source, unrelated to overall space under a bench.

That's what ETI says now about 4-Li batteries. They don't delete the battery box (yet). In Nov 2020, 4-Li batteries was an option on their old configuration guide when we first looked it over. We were disappointed when that option disappeared, but understand things better now.
We opted for the widened rear bench option for the added space that offers.

[DanK]

Centex,I will be getting my trailer this coming January. I was not the person that eti said no to the single 200 amp battery. I have decided to get the trailer "lithium ready " and just exploring the possibility of battery configuration. I am going to wait a year or more to switch to a lithium as we live in south Florida and will retire in 2 years . The next year or two will be in state parks with electric hook ups . Dakota and renorgy are the brands that pop up the most frequently and I was just wondering what the positive and negatives a single larger battery versus 2 batteries would be.

[Craiger]

From the hints that escape management is dropping. I think there's going to be an upgrade of the battery capabilities. I believe the goal would be to enable the running of the air conditioning system by battery alone.

[cpaharley2008]

Originally Posted by Craiger

From the hints that escape management is dropping. I think there's going to be an upgrade of the battery capabilities. I believe the goal would be to enable the running of the air conditioning system by battery alone.

That may not be desirable to some......

[splitting_lanes]

Originally Posted by Centex

Dan, can you provide the make/model for whatever ~200Ah LiFePO4 battery / batteries have caught your eye? Even better, a link to the webpage or specs?

Did ETI say exactly why "too large"? One factor to remember is that, for reasons that we don't need to rehash here, ETI insists on installing even LiFePO4 batteries in a sealed box vented to the exterior. It's possible that their "too large" relates to the sealed-boxes they are willing to source, unrelated to overall space under a bench.

Are you willing to consider post-delivery DIY solutions or only solutions that ETI will implement (sorry, not sure if the E21c in your profile is in your hands now or yet to-be-delivered, or maybe these questions in the context of a different trailer)?

I asked about a 200AH battery that was 19” long, if I recall correctly, and here was their response:

Hello Rick

These batteries are too long. The battery size that we know fits is 12.9”L x 7”W x 9.2”H They need to fit into this dimensions.

Warm Regards

Melisa Weinert, Customer Service

Escape Trailer Industries LP.

[Brian B-P]

Originally Posted by DanK

Let's say the largest power draw item I plan on ever using is a microwave hooked up to a 2000 watt inverter , do I need more then a hundred amps of continuous discharge . Sorry electric is not one of my strong points

An inverter putting out 2000 watts will take in more than that... let's say 2200 watts. At 12 volts that's 183 amps.

Of course just because the inverter can produce 2000 watts, doesn't mean that an appliance will use that. A typical high-power microwave oven puts out 1200 watts of microwave power, using about 1500 watts of electricity to do it. With inefficiency again, a guess might be 1700 watts into the inverter; at 12 volts that's 142 amps.

100 amps at 12 volts into an inverter would be 1200 watts, and with inverter ineffiency that would be less than 1100 watts of AC power out of the inverter... so appliances totalling less than that could run on about 100 amps of 12 volts DC into the inverter from the battery.

[Jack!]

Originally Posted by Brian B-P

Of course just because the inverter can produce 2000 watts, doesn't mean that an appliance will use that.

Guessing a bit here, as we don't have the trailer yet, but thought I saw someplace that ETI uses a 700 watt MWave, thus the GP 1500 watt inverter.
Convection MWave is differently a no-go.

[Kirt]

Originally Posted by Jack!

Guessing a bit here, as we don't have the trailer yet, but thought I saw someplace that ETI uses a 700 watt MWave, thus the GP 1500 watt inverter.
Convection MWave is differently a no-go.

We have a 700 watt microwave but that was the output rating. It actually draws about 1150 watts on the input side. Add the inverter load and it's about 105 amp draw from the batteries.
I went down this rabbit hole a while back . . . .

The 1500 watt inverter is still fine.

[alanmalk]

Originally Posted by DanK

...
Dakota and renorgy are the brands that pop up the most frequently and I was just wondering what the positive and negatives a single larger battery versus 2 batteries would be.

The responses above should give you a good indication that a single 100 Ah battery - either Lithium or lead-acid - would be borderline to power an inverter/microwave combination. The lead-acid would suffer from voltage sag and the Lithium would stress the battery management system (BMS). A single larger battery, say 200 Ah, may not be the solution either since Escape may not want to install an oversize battery, and many cheaper Lithium batteries limit output to 100 Ah even in the larger sizes. Best solution at present is a pair of batteries in parallel, which will double your available continous amp output. Reheat that pizza with confidence!

Your choice of brands - Dakota, Renogy or BattleBorn - all get high ratings. I have the first two - for different applications. The Renogy are cheaper but oddly designed. Given a choice I fall for cheap every time - a genetic defect I believe.

[Brian B-P]

Originally Posted by Jack!

Guessing a bit here, as we don't have the trailer yet, but thought I saw someplace that ETI uses a 700 watt MWave, thus the GP 1500 watt inverter.
Convection MWave is differently a no-go.

The current ETI-supplied microwave oven might be rated at 700 watts output (so it would use at least 850 watts AC or more, and thus perhaps 1000 watts DC), but they have used various models and an owner can install something different.

It's not just micro-convection ovens that use high power - my non-convection microwave at home has 1200 watts output and 1450 watts input.

[Jack!]

Originally Posted by Kirt

We have a 700 watt microwave but that was the output rating. It actually draws about 1150 watts on the input side. Add the inverter load and it's about 105 amp draw from the batteries.
I went down this rabbit hole a while back . . . .
The 1500 watt inverter is still fine.

Yeah. Have to wait to see what ETI uses this Feb on our build Thinking ETI has in mind a MW that plays nice with the inverter they install.
Our battery bank capacity will be 400amps and can do a surge of 800amps for 30secs. We could do a bigger inverter if more power is needed but going for more duration at lower power.

[Jack!]

Originally Posted by Brian B-P

The current ETI-supplied microwave oven might be rated at 700 watts output (so it would use at least 850 watts AC or more, and thus perhaps 1000 watts DC), but they have used various models and an owner can install something different.

It's not just micro-convection ovens that use high power - my non-convection microwave at home has 1200 watts output and 1450 watts input.

Indeed. Our home unit would be useless in the trailer. Too power hungry and wouldn't fit, as well. Have the option to go bigger on the inverter, but will wait & see what MW they give us. Want to try to make the 1500 work for us. Planning on more propane and very little MW in any case.

[dstreight]

I put together a 400A/6500W LiFePO4 battery in 4S5P (4-Series x 5-Parallel) using Fortune aluminum cased cells from Electric Car Parts Co for our all electric 15A a couple years ago. I, per their recommendation, used 4 balancers for the 4S groups and all has been great since.

Not being an expert all things batteries, I wonder if coupling multiple batteries with their own BMS would be an OK strategy/performance versus one BMS + balancers for one "battery"?