Changing to a Litime 12 v 100ah battery
- Thread starter vincemike
- Start date
david-steph2018
Well-known member
It depends on the converter that is installed. Some converters will be able to be switched for lithium batteries from AGM or flooded cell. You need to find out which converter you have installed in the rig.
Switching to a LiFePO4 (Lithium Iron Phosphate) battery like the Litime 12V 100Ah offers significant improvements over traditional lead-acid batteries in RVs and other applications. Here's what you need to know about making the switch:
Benefits of LiFePO4 Batteries
Long Life: LiFePO4 batteries typically last much longer than lead-acid batteries, often providing over 2000 charge cycles compared to 300-500 charge cycles for lead-acid batteries.
Lightweight: Significantly lighter than lead-acid batteries, an advantage for RVs where weight is an important consideration.
High Efficiency: Higher energy density and efficiency mean you get more usable power from a LiFePO4 battery than a lead-acid battery of the same size.
Faster charging: LiFePO4 batteries can charge faster and accept higher charging currents, making them beneficial for use in RVs where fast charging makes sense.
Superior Performance: Provides superior performance over a wider temperature range and has a lower self-discharge rate.
Replacement Considerations
Battery Management System (BMS): LiFePO4 batteries typically have a built-in BMS to protect against overcharging, over-discharging, and overheating. Make sure the battery you select has a good BMS.
Charging System: Make sure your existing charging system is compatible with LiFePO4 batteries. You may need to adjust or replace your charger to fit the charging profile required for LiFePO4.
Installation: Make sure the new battery will fit in the space and the connectors are compatible. LiFePO4 batteries often have a different connection configuration than lead-acid batteries.
Weight and Space: Measure the available space and weight capacity of your RV or application to make sure the new battery will fit and will not affect balance or load.
Cost: LiFePO4 batteries typically have a higher initial cost than lead-acid batteries, but the long-term savings and performance benefits often outweigh the initial cost.
Replacement Procedure
Remove the Old Battery: Safely disconnect and remove the old lead-acid battery from the system.
Install a New Battery: Place the LiFePO4 battery in the battery compartment and make the necessary connections. Check the battery polarity and install it correctly.
Adjust Settings: If necessary, update the settings on the charger and all associated devices to meet the requirements of the LiFePO4 battery.
Test System: Check the system to make sure everything is working properly and that the battery is charging properly.
Benefits of LiFePO4 Batteries
Long Life: LiFePO4 batteries typically last much longer than lead-acid batteries, often providing over 2000 charge cycles compared to 300-500 charge cycles for lead-acid batteries.
Lightweight: Significantly lighter than lead-acid batteries, an advantage for RVs where weight is an important consideration.
High Efficiency: Higher energy density and efficiency mean you get more usable power from a LiFePO4 battery than a lead-acid battery of the same size.
Faster charging: LiFePO4 batteries can charge faster and accept higher charging currents, making them beneficial for use in RVs where fast charging makes sense.
Superior Performance: Provides superior performance over a wider temperature range and has a lower self-discharge rate.
Replacement Considerations
Battery Management System (BMS): LiFePO4 batteries typically have a built-in BMS to protect against overcharging, over-discharging, and overheating. Make sure the battery you select has a good BMS.
Charging System: Make sure your existing charging system is compatible with LiFePO4 batteries. You may need to adjust or replace your charger to fit the charging profile required for LiFePO4.
Installation: Make sure the new battery will fit in the space and the connectors are compatible. LiFePO4 batteries often have a different connection configuration than lead-acid batteries.
Weight and Space: Measure the available space and weight capacity of your RV or application to make sure the new battery will fit and will not affect balance or load.
Cost: LiFePO4 batteries typically have a higher initial cost than lead-acid batteries, but the long-term savings and performance benefits often outweigh the initial cost.
Replacement Procedure
Remove the Old Battery: Safely disconnect and remove the old lead-acid battery from the system.
Install a New Battery: Place the LiFePO4 battery in the battery compartment and make the necessary connections. Check the battery polarity and install it correctly.
Adjust Settings: If necessary, update the settings on the charger and all associated devices to meet the requirements of the LiFePO4 battery.
Test System: Check the system to make sure everything is working properly and that the battery is charging properly.
Attachments
Thank you ,, I was hoping I wouldn’t have change it
I tested my converter and it is charging 13 volts to my battery would it damage the Grade A+ LiFePO4 Battery: LiTime 12V100Ah BCI Group 31 LiFePO4 Lithium batterie
david-steph2018
Well-known member
I don't know if that will charge the battery to 100%. I was looking on their website and it says:
"To charge 12V battery, it is recommended to use 14.6V battery charger.
The Recommended Charging Voltage: 14.2V - 14.6V."
https://www.litime.com/products/litime-12v-100ah-lithium-lifepo4-battery
This under FAQ section, 7th question down on the list.
Thank you
taskswap
Well-known member
You can't over-charge a properly manufactured LifePO4 battery unless you go nuts and throw like 30V at it. This is because they are not simple "water tanks" for electricity like lead-acid batteries are. They have internal controllers that manage their state. In fact, they are not one battery. They are usually 4 (for a 12V battery) 3.2V smaller batteries wired in series internally (that's where most spec sheets get their 12.8V "nominal" voltage from - 4 * 3.2 = 12.8).
These internal cells actually need to be balanced as well, because it's bad for the performance of the battery if your cells are at, say, 3.1V, 3.0V, 2.9V, 3.2V. The battery management system (BMS) inside the battery handles this for you so you don't need to think about it (again, if it's a quality battery). In addition to managing charging, the BMS will do other things like cut off the battery if you short it (over-current protection), if it's too cold or hot (low-temp charging disconnect), and so on.
This is what a typical one looks like inside - you can see the four blue battery cells plus the charge controller and its four wires to the cells plus things like temp sensors.
I don't know the battery you're referring to and it's not like there's a database of "well made batteries" to look it up on. Will Prowse on Youtube (among others) regularly does teardowns of batteries, and you might get lucky and find yours reviewed there. Even expensive batteries can be made badly, and he regularly will show things like poor solder connections, non-working temperature sensors, etc that can cause them to fail quickly even if they work at first. But let's assume yours is good.
For the BMS to do its job, it takes a bit of power itself. Think of two balloons. Connect them with a straw. The pressure between them will equalize and they will be the same size. Suppose you want to "charge" one balloon from the other. The balloon you want to charge from must start out bigger (a bit higher voltage) or the target ballon won't inflate. It will just sit there. To fill balloon A, balloon B must start with more air in it.
If the target balloon is very small (your RV battery is discharged) then any source balloon will inflate it - somewhat. This is what your current converter will do. If it puts out 13V and your battery is at say 11.8V, it will charge it at least somewhat. But to get it to 100% you usually need the charger to be at least 1-2V above the target you're trying to reach. The 12.8V rating on your battery is usually just a "nominal" value. To be at 100%, most "12V" LifePO4 batteries actually need to hit 13.6V. Your battery should have come with a spec sheet identifying its "boost" voltage, which is usually about 1V above that, or 14.4-14.8V (check your spec sheet).
There are add-on products that can help here, such as "DC to DC charger" units. Here's an example of one that lots of folks use in trailers where their trucks don't put out enough juice to charge their trailers while they drive: https://www.amazon.com/Renogy-Battery-Batteries-Multi-stage-Charging/dp/B07Q5VYPCF
These options can help but aren't very smart. They won't hurt the battery because the BMS will protect it, but a proper charge controller designed for lithium batteries will give you more capacity per charge and more life out of the battery. Instead of just constantly supplying that high charge voltage, they'll run a charging "algorithm" that usually starts at some high value ("boost") and then drops to a lower one ("float") as the battery nears full charge
In my personal opinion (and worth every penny you paid), I think the best thing anyone can do when installing a lithium battery is add solar. MPTT solar charge controllers are designed specifically to deal with this challenge and to do it efficiently. They're usually very configurable, too, so instead of just setting a "lead acid vs. lithium" switch (like many RV converters sold today) you can set it up exactly per your battery's spec sheet and maximize your battery capacity AND lifetime simultaneously. They're cheap (many very good units run $80-$140), easy to install, and require no change to your existing converter. Plus you get all the side benefits - never a flat battery while your rig is in storage, extra power if you need to spend a night at a Walmart on a long trip (with no shore power or generator), etc.
You don't need 1200W of solar on your roof, either. These chargers are smart. If you're on shore power or a generator, and your converter is putting out 30A charging your battery, the MPTT will just contribute what it can. As your battery gets full to where your converter can't add more to the equation, the MPTT will take you over the top. Even a single 200W panel is better than nothing.
These internal cells actually need to be balanced as well, because it's bad for the performance of the battery if your cells are at, say, 3.1V, 3.0V, 2.9V, 3.2V. The battery management system (BMS) inside the battery handles this for you so you don't need to think about it (again, if it's a quality battery). In addition to managing charging, the BMS will do other things like cut off the battery if you short it (over-current protection), if it's too cold or hot (low-temp charging disconnect), and so on.
This is what a typical one looks like inside - you can see the four blue battery cells plus the charge controller and its four wires to the cells plus things like temp sensors.
I don't know the battery you're referring to and it's not like there's a database of "well made batteries" to look it up on. Will Prowse on Youtube (among others) regularly does teardowns of batteries, and you might get lucky and find yours reviewed there. Even expensive batteries can be made badly, and he regularly will show things like poor solder connections, non-working temperature sensors, etc that can cause them to fail quickly even if they work at first. But let's assume yours is good.
For the BMS to do its job, it takes a bit of power itself. Think of two balloons. Connect them with a straw. The pressure between them will equalize and they will be the same size. Suppose you want to "charge" one balloon from the other. The balloon you want to charge from must start out bigger (a bit higher voltage) or the target ballon won't inflate. It will just sit there. To fill balloon A, balloon B must start with more air in it.
If the target balloon is very small (your RV battery is discharged) then any source balloon will inflate it - somewhat. This is what your current converter will do. If it puts out 13V and your battery is at say 11.8V, it will charge it at least somewhat. But to get it to 100% you usually need the charger to be at least 1-2V above the target you're trying to reach. The 12.8V rating on your battery is usually just a "nominal" value. To be at 100%, most "12V" LifePO4 batteries actually need to hit 13.6V. Your battery should have come with a spec sheet identifying its "boost" voltage, which is usually about 1V above that, or 14.4-14.8V (check your spec sheet).
There are add-on products that can help here, such as "DC to DC charger" units. Here's an example of one that lots of folks use in trailers where their trucks don't put out enough juice to charge their trailers while they drive: https://www.amazon.com/Renogy-Battery-Batteries-Multi-stage-Charging/dp/B07Q5VYPCF
These options can help but aren't very smart. They won't hurt the battery because the BMS will protect it, but a proper charge controller designed for lithium batteries will give you more capacity per charge and more life out of the battery. Instead of just constantly supplying that high charge voltage, they'll run a charging "algorithm" that usually starts at some high value ("boost") and then drops to a lower one ("float") as the battery nears full charge
In my personal opinion (and worth every penny you paid), I think the best thing anyone can do when installing a lithium battery is add solar. MPTT solar charge controllers are designed specifically to deal with this challenge and to do it efficiently. They're usually very configurable, too, so instead of just setting a "lead acid vs. lithium" switch (like many RV converters sold today) you can set it up exactly per your battery's spec sheet and maximize your battery capacity AND lifetime simultaneously. They're cheap (many very good units run $80-$140), easy to install, and require no change to your existing converter. Plus you get all the side benefits - never a flat battery while your rig is in storage, extra power if you need to spend a night at a Walmart on a long trip (with no shore power or generator), etc.
You don't need 1200W of solar on your roof, either. These chargers are smart. If you're on shore power or a generator, and your converter is putting out 30A charging your battery, the MPTT will just contribute what it can. As your battery gets full to where your converter can't add more to the equation, the MPTT will take you over the top. Even a single 200W panel is better than nothing.
After some research , correct me if I’m wrong
I should treat my onboard battery charger as a solar panel connected to the positive and negative to the PV side of the MPPT 100/30 charge controller and positive and negative to the battery
If this is correct I will add posts to connect additional solar panels . I saw some diagrams with fuses and wire sizing
Would the Vistron Energy 100/30 charge control work ?
Thank you
taskswap
Well-known member
Sorry, just to clarify, you would not connect solar panels directly to anything. They run at a different voltage from the rest of your system, typically something like 20V nominal per panel and a lower current. You need an MPTT charger which will have an input specifically for solar and an output that you can tie directly to your system (battery) as I think you're describing. An MPTT charger will both convert what the solar panels put out to something your batteries can use, as well as (typically, for a quality product like a Renogy, EPEver, etc) having programming inside it to maximize what your batteries can do.
You do not need any of this. Your existing converter WILL work, it will just almost certainly not be able to charge your new lithium batteries to 100% capacity (it might be lucky to even hit 80%). Solar is also not necessary here, it's just a cheap hack. If you're going to spend money on anything, why not spend it on something that solves the problem AND gives you other benefits? Not counting installation, an entry-level 220W panel is like $180 on Amazon right now, and MPTT chargers start at like $80. That's pretty comparable to (if not even cheaper than) other solutions like adding DC-DC converters or replacing your existing load center for a smarter one, so why not at least consider it if you can?
You do not need any of this. Your existing converter WILL work, it will just almost certainly not be able to charge your new lithium batteries to 100% capacity (it might be lucky to even hit 80%). Solar is also not necessary here, it's just a cheap hack. If you're going to spend money on anything, why not spend it on something that solves the problem AND gives you other benefits? Not counting installation, an entry-level 220W panel is like $180 on Amazon right now, and MPTT chargers start at like $80. That's pretty comparable to (if not even cheaper than) other solutions like adding DC-DC converters or replacing your existing load center for a smarter one, so why not at least consider it if you can?
taskswap
Well-known member
I mean... this is a very personal opinion but I like the Harbor Freight Predator (I use the 3500W). Here's the thing. Most generators are designed for about 10-20h of run-time per year. Backups for houses. That doesn't mean you can't run them longer, especially with better ($$$) brands, but they often do have high failure rates if you use them regularly. The HF generator is nothing special but definitely not bad, either. But here's the thing. There's a store a half-hour from almost anywhere-USA, and often in places where it's hard to even find a Home Depot or Costco (where folks like us often camp). Buy the insurance, and if you have an issue, just go to the nearest store and get a new one.
