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Is this a great deal on LiFePO4 batteries? IDK for sure so please tell me...

wired1

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Looks fair to me. The convenience of not having to wait 3 months for delivery from china is a major plus. Search reviews for that particular battery. I'm building a 230 battery and after buying the parts I'll have about $600 into it.
 

Here is a List of all Will's Battery Tear Downs. NOTE THE DATES, darn thing can't sort by date :-(
Remember that companies change what they build and sell, so older reviews / teardowns may not apply to current offerings.
* Exception being BattleBorn, SimpliPhi and the like, "Big Commercial producers" are more consistent over time.

BTW: from the description of that AmpereTime 12V/200AH pack. They are using 100AH cells with 8S2P (2 cells in parallel) configuration, hence why the BMS is only 100A Discharge / 50A Charge rate. Unless the cells are Perfectly Matched & Batched that is not good. THIS MODEL HAS BEEN REPLACED ! I would not buy an old model that is discontinued.

This is the New Model: $980 USD + S&H

Ampere Time 12V 200Ah|2560W Power | Lithium|LiFePO4 | Deep Cycle Rechargeable Battery,
Built-in 200A BMS,400A Max, 4000~8000 Cycles, Perfect for Solar Home, RV/Camping, Off-Grid Applications

FYI:
8x EVE-280AH Matched Cells = $125ea, $1000 for the set of 8 (Luyuan Tech)
1x Smart 8S-BMS = $200 (average)
1x 250A MRBF Fuse = $30 (BlueSea/Bussman)
Box/Casing $50 to be polite.
2x 3/8" Solid Brass (plated) Battery Terminals for case $30
Total: for 24V/280AH/7.1kWh $1320 USD 8 Cells.
Total: for 12V/280AH/3.584 kWh = $820 USD 4 Cells.


202AH CATL Lifepo4 @ 72.90ea. Also at Luyuan.
 
BTW: from the description of that AmpereTime 12V/200AH pack. They are using 100AH cells with 8S2P (2 cells in parallel) configuration, hence why the BMS is only 100A Discharge / 50A Charge rate. Unless the cells are Perfectly Matched & Batched that is not good. THIS MODEL HAS BEEN REPLACED ! I would not buy an old model that is discontinued.
Thanks,
I did watch his videos and that was the reason I bought the batteries. It was so close to the same money for AGM batteries I thought it was the better choice as it was the top of my budget for them. I don't really understand the charge rates and how that will matter to me? I'm only using these right now as emergency backup and will recharge from the grid or generator at first. Can you elaborate on the rates?
I know there's a newer model but out of my budget. I see many people buying even used cells so I thought these would be ok for me.
 
All batteries have a C-Rating that we refer to for charge/discharge values.
LFP cells in general, have a 1C Rate for Discharge and a 0.5C Rate for charging.
A 200AH LFP cell (not battery pack but individual cell) can handle a 1C discharge rate which is 200A output and a .5C rate or 100A Charge Input.
If a battery pack (complete assembly) is built with Genuine 200AH cells, the complete battery will operate with the limits on the line above.
If a Battery is built with 100AH cells that are paralleled THEN the Discharge Rate will be limited to 1C/100A and the charge rate will be .5C/50A.

Yeah it is a bit confusing at first blush ! There is a LOT of info to absorb and sadly a gotcha in this, is that FLA (Lead Acid) battery language is similar, it is not the same exactly. This ultimately creates confusion as terms are applied differently. I really had to wrap my brain around that because I started with big Lead Acid and now also have a large LFP bank as my primary.

These older generation batteries are likely fine BUT one thing to be certain of with such prebuilts, be "conservative" and "reasonable".
Charging these, the profile should be "modest" so as to not stress or push the battery pack.
You can push up to 50A charge rate at the battery but NOT more ! Conservative would say limit that to 40A.
The working Voltage Curve for LFP is 3.000-3.450V per cell. So for 12V system 12.0V to 13.8V which is just a hair over 90% of total capacity.
The functional voltage range is 2.500-3.650. LFP will always settle from 3.650 to 3.550 within an hour on average. This is normal.

• Bulk/Absorption: 14.0V (3.500 vpc)
• Absorption Time: 15 minutes per 100Ah of battery bank
• Float: 13.4V – 13.8V (3.350-3.450 vpc)
• Equalization: Disabled
• Temperature Compensation: Disabled
* vpc = Volts per Cell based on standard rules.
** It is often said that FLOAT is not needed or wanted. Float is NOT topping the cells at 100%, it is Constant Voltage and floating current, this is used by the BMS during it's internal balancing process as it sits, this allows the cells internally to all level up identically. This also compensates for the bit lost during Passive Balancing which only burn off hi voltage. Not all BMS' have such capabilities but I recall that the AmpereTime had passive. (could be only certain models, can't say for sure)

Inverter Cut Off points should be 10.4V (2.600vpc) for Low Volt cutoff and 14.4V (3.600vpc) for Hi Volt cutoff. Same applies to other gear like SCC etc.
See the link to the LFP Voltage Chart in my signature.

You have not mentioned with WHAT you are charging. Do you have an Inverter/Charger, an Inverter & separate Charger or what. You CANNOT use a 12V port from a genset to charge such a battery ! Few tried and it never ended well. DO NOT USE a Car Battery Charger ! NEVER !!

A VERY IMPORTANT POINT which is often neglected.
Any Lithium Battery system is far more sensitive than the old abusable Lead. You will see how I note 2.600v or 3.450v per cell, it is because it is THAT sensitive. Yep, millivolts add up and fast. Also realize that 90% of the AH Stored sits between 3.000-3.400vpc. Ensuring that the system is clean & calibrated is essential so that things do not go wrong. All Lithium is intolerant of any abuse. What this means, is when you setup your Inverter/Charger and other devices, you will have to correct & calibrate the voltages so that when the Inverter sees 13.900 that it really is 13.900 and NOT 14.2 because there is line loss and it will overrun the battery.
- See link in my signature regarding Calibration. You'd be surprised how many do not do it and wonder why things go kaflooie in the worst of ways.

Think of it this way: Old Lead Acid was abusable and tolerated a fair bit actually BUT it is considered "Analog Tech". Lithium Systems are the next generation and "Digital Tech" and as such far more sensitive to things like voltage deviations etc.

Hope it helps and answers your questions without too much confusion.
Sorry, I prefer to provide a more detailed response because who knows who will be reading the thread later and what their knowledge/experiences are.

BTW: Highly suggested Reading: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
 
Thanks,
I did watch his videos and that was the reason I bought the batteries. It was so close to the same money for AGM batteries I thought it was the better choice as it was the top of my budget for them. I don't really understand the charge rates and how that will matter to me? I'm only using these right now as emergency backup and will recharge from the grid or generator at first. Can you elaborate on the rates?
I know there's a newer model but out of my budget. I see many people buying even used cells so I thought these would be ok for me.
The issue (as I see it) is that it would take 4+ hours to charge your battery at its max charge rate (200ah battery / 50amps MAX charge = 4 hours, at best) and you are limited to around 1200 watts of inverted AC max (12.8 battery volts * 100 amps max from BMS = 1280 watts), and that's running the BMS at 100%. It would be safer to keep it well under 1000 watts so you don't overload or overheat the BMS.

Depending on specific usage, it might be fine. But charging will be slower, and your ceiling for discharge amperage would be somewhat low too.
 
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You have not mentioned with WHAT you are charging. Do you have an Inverter/Charger, an Inverter & separate Charger or what. You CANNOT use a 12V port from a genset to charge such a battery ! Few tried and it never ended well. DO NOT USE a Car Battery Charger ! NEVER !!
Wow, thanks Steve, lots of info for me to sort through! My idea was to buy whatever I find is the proper charger/ inverter and to hopefully be able to power that charger through my Honda I2200 generator or the grid when it comes back up. I just am not sure where to start on the inverter/charger. I had originally bought a 12 volt 1000 watt inverter as I was excited to be able to have some comfort through my 100 watt car cigarette lighter inverter to run a couple of fans during a recent outage. I plan on returning that 1000 watt inverter now and have to figure out where to go next! I was told I would be better off with a 24 volt inverter.
I do plan in a year or two to add PV panels to keep these charged but I can't do that right now.

Does anyone feel I really goofed buying these batteries as I could cancel the order if I act quickly?

I was all set to go with AGM's but for very close to the same money to get over 3500 usable watts, I thought these were a better choice..
 
The issue (as I see it) is that it would take 4+ hours to charge your battery at its max charge rate (200ah battery / 50amps MAX charge = 4 hours, at best) and you are limited to around 1200 watts of inverted AC max (12.8 battery volts * 100 amps max from BMS = 1280 watts), and that's running the BMS at 100%. It would be safer to keep it well under 1000 watts so you don't overload or overheat the BMS.

Depending on specific usage, it might be fine. But charging will be slower, and your ceiling for discharge amperage would be somewhat low too.
Is that a long time to charge? The other thing is I doubt my draw would ever exceed 1000 watts. Possibly if I had both of my refrigerators start at once, they have a starting draw of 705 watts. When you mention I am limited to 1200 watts of inverted AC, do you mean when charging?

Sorry for all the questions but I have a lot to learn...

I am only planning to use this system right now once or twice a week during a rolling blackout that we're seeing and then charge back off the grid or the generator during the day, when I won't mind hearing the generator so much.
.
 
All batteries have a C-Rating that we refer to for charge/discharge values.
LFP cells in general, have a 1C Rate for Discharge and a 0.5C Rate for charging.
A 200AH LFP cell (not battery pack but individual cell) can handle a 1C discharge rate which is 200A output and a .5C rate or 100A Charge Input.
If a battery pack (complete assembly) is built with Genuine 200AH cells, the complete battery will operate with the limits on the line above.
If a Battery is built with 100AH cells that are paralleled THEN the Discharge Rate will be limited to 1C/100A and the charge rate will be .5C/50A.

Yeah it is a bit confusing at first blush ! There is a LOT of info to absorb and sadly a gotcha in this, is that FLA (Lead Acid) battery language is similar, it is not the same exactly. This ultimately creates confusion as terms are applied differently. I really had to wrap my brain around that because I started with big Lead Acid and now also have a large LFP bank as my primary.

These older generation batteries are likely fine BUT one thing to be certain of with such prebuilts, be "conservative" and "reasonable".
Charging these, the profile should be "modest" so as to not stress or push the battery pack.
You can push up to 50A charge rate at the battery but NOT more ! Conservative would say limit that to 40A.
The working Voltage Curve for LFP is 3.000-3.450V per cell. So for 12V system 12.0V to 13.8V which is just a hair over 90% of total capacity.
The functional voltage range is 2.500-3.650. LFP will always settle from 3.650 to 3.550 within an hour on average. This is normal.

• Bulk/Absorption: 14.0V (3.500 vpc)
• Absorption Time: 15 minutes per 100Ah of battery bank
• Float: 13.4V – 13.8V (3.350-3.450 vpc)
• Equalization: Disabled
• Temperature Compensation: Disabled
* vpc = Volts per Cell based on standard rules.
** It is often said that FLOAT is not needed or wanted. Float is NOT topping the cells at 100%, it is Constant Voltage and floating current, this is used by the BMS during it's internal balancing process as it sits, this allows the cells internally to all level up identically. This also compensates for the bit lost during Passive Balancing which only burn off hi voltage. Not all BMS' have such capabilities but I recall that the AmpereTime had passive. (could be only certain models, can't say for sure)

Inverter Cut Off points should be 10.4V (2.600vpc) for Low Volt cutoff and 14.4V (3.600vpc) for Hi Volt cutoff. Same applies to other gear like SCC etc.
See the link to the LFP Voltage Chart in my signature.

You have not mentioned with WHAT you are charging. Do you have an Inverter/Charger, an Inverter & separate Charger or what. You CANNOT use a 12V port from a genset to charge such a battery ! Few tried and it never ended well. DO NOT USE a Car Battery Charger ! NEVER !!

A VERY IMPORTANT POINT which is often neglected.
Any Lithium Battery system is far more sensitive than the old abusable Lead. You will see how I note 2.600v or 3.450v per cell, it is because it is THAT sensitive. Yep, millivolts add up and fast. Also realize that 90% of the AH Stored sits between 3.000-3.400vpc. Ensuring that the system is clean & calibrated is essential so that things do not go wrong. All Lithium is intolerant of any abuse. What this means, is when you setup your Inverter/Charger and other devices, you will have to correct & calibrate the voltages so that when the Inverter sees 13.900 that it really is 13.900 and NOT 14.2 because there is line loss and it will overrun the battery.
- See link in my signature regarding Calibration. You'd be surprised how many do not do it and wonder why things go kaflooie in the worst of ways.

Think of it this way: Old Lead Acid was abusable and tolerated a fair bit actually BUT it is considered "Analog Tech". Lithium Systems are the next generation and "Digital Tech" and as such far more sensitive to things like voltage deviations etc.

Hope it helps and answers your questions without too much confusion.
Sorry, I prefer to provide a more detailed response because who knows who will be reading the thread later and what their knowledge/experiences are.

BTW: Highly suggested Reading: https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
So Steve, if I wire these in series, do I still need to keep the charge rate below 40 amps or is it double to 80 amps? Can you recommend a all in one that I can add PV to in the future?
 
Personally for safety concern, I would not exceed the Charge Amperage capability that 1 Battery can accept.
I do not use an AIO but I know that many use MPP-Solar, Growatt with good success.

A Good start is Will's site pages:
Here's his playlist of reviews & installs (look at the dates too, some are fairly old).
 
Arriving Jun 9 - Jun 14


2
12V 200Ah Lithium Iron LiFePO4 Deep Cycle Battery, Built-in 100A BMS, 2000+ Cycles, 280amp Max, Perfect for RV, Solar, Marine, Overland, Off-Grid Application;
Sold by: Ampere Time US
There was an additional coupon for $39.20 bringing the total to 1528.78. This seems to be WAY less than I've seen for 400AH of LiFePO4. Am I missing something guys??

$783.99
Business Price
Condition: New
12V, 200Ah, but 100Ah BMS.........is this what you need?
 
Just noticed some Renogy's showed up at batterhookup, as an FYI

 
Just noticed some Renogy's showed up at batterhookup, as an FYI

I wonder why these can't be wired in series? I was told I'm much better off with a 24V system?
 
More than likely, it's the BMS. The cells could be wired in any config you wanted, but these pre-built batteries are using a BMS and most of these import BMS makers aren't set up for Series connections. And yes, you are much better off with 24v system. 48v even better still as the amp draw of your appliances will be cut in half for 24v, etc.
 
Is that a long time to charge? The other thing is I doubt my draw would ever exceed 1000 watts. Possibly if I had both of my refrigerators start at once, they have a starting draw of 705 watts. When you mention I am limited to 1200 watts of inverted AC, do you mean when charging?
4 hours isn't TOO long, and a 40-50 amp charger isn't as expensive as a high(er) power unit, so that's can be seen as a bonus. A lot of similar sized DIY battery packs (and some other store-bought packs) can take 100+ amps, which cuts charge times down considerably.

The "inverted ac" I was talking about would be how much AC current you could pull out of an attached inverter (like your fridges).

As to why the Renogy batteries won't go in series, the internal BMS units aren't capable of doing that. Each cell has a 12 volt BMS, and wired in series would push 24 volts through the same unit. Some can handle it, some can not.
 
I believe so. Hoping I'm right. My max load will be under 2000 watts and my 8 hour load will be around 3,000 watts total. I am only trying for 8 hours of backup w/o my generator running. I will be adding solar panels in about a year.
I meant by 100Ah limit on BMS, not the total battery capacity.
 
Renogy = Run Away !
Just search for ALL the issues with ANYTHING renogy. From DOA to no support/service to excuses of every sort to non-communications and even failure to deliver what is ordered and argue about it, rather than make it right... Ignore the stuffed reviews.
 
even failure to deliver what is ordered and argue about it, rather than make it right.
I ordered two Renogy 100AH Lithium through Lowes on 21 May 2021. On Lowes website, it said batteries are shipped, but Lowes customer service and I can not tracked it through Fedex. The expected delivery date keeps changing everytime I check.
 
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