drivesafe
29th May 2021, 04:11 PM
How do you select the best value Lithium Battery?
A heads-up on my connection to lithium batteries.
I am “NOT” an expert on lithium batteries but I have been working with them for just over a decade now.
This included testing a large number of them and taking a couple of lithium batteries to the point where they were damaged, as requested by the supplier, so that they had a genuine idea of what their batteries could safely tolerate.
While I no longer sell lithium batteries, I still have a number of lithium batteries in my workshop, and I still carry out a fair amount of testing and I use these batteries as the Set-Point to compare with other lithium batteries.
From experience, so called “NAME” brands mean nothing, and neither does comparing Price vs Amp Hours. A common practice but falls short of anything meaningful.
The following is how I sort out good from not so good Lithium batteries and whether you follow this is completely up to you as the buyer.
First and foremost, get the specs for the battery. If there are no specs, or very limited specs, I personally avoid those batteries.
The specs need to include :-
“USABLE” Ah ( Amp Hours ) not just the total Ah.
Cycle rate to the lowest recommended DoD ( Depth of Discharge )
Optimum and maximum charge current.
Optimum and maximum “CONTINUOUS” discharge current.
Operating temperature range. While not as important as this should not be a problem in Australia but it is still a good idea to be sure the battery will be usable in RV conditions.
I also make sure the warranty period is no less than 3 years.
I have no intentions of using a lithium battery as a cranking battery, and nor do I intend to put one in an engine bay, and while this is a personal choice, it also governs where the battery is to be used.
My choice for seeing what value for money a given lithium battery is, is to compare Throughput to cost.
To do this, first get the cycle rate at the lowest DoD and multiply this by the amp hours at that DoD.
For instance, if a battery specs for a 100Ah lithium battery state that that particular battery can be cycled down to 80% DoD 2,000 time, then the Throughput for that battery 80 x 2,000, or 160,000 AMPERES.
If this battery cost $850, divide the 160,000 by 850 and you get the USABLE amperes per dollar, over the lifespan of the battery.
Here are some examples.
A Fusion V-LFP-12-100, a 100Ah Lithium battery can be cycles down to 100% DoD 1,600 times and with a cost of $998, this battery has a USABLE amperes per dollar value of 160.
A Solarking CB-100-12-100, another 100Ah Lithium battery can be cycles down to 100% DoD, 2,000 times and can be bought for $588, giving this battery has a USABLE amperes per dollar value of 340.
An Enerdrive EPL-100-12VLITE, another 100Ah Lithium battery can be cycles down to 80% DoD, 2,000 times and can be bought for $869, giving this battery has a USABLE amperes per dollar value of 178.
A Redarc LBAT12100, another 100Ah Lithium battery can be cycles down to 80% DoD, 2,000 times and can be bought for $1,498, giving this battery has a USABLE amperes per dollar value of 107.
Just beware, along with the USABLE amperes per dollar, you still have to consider maximum charge and maximum discharge characteristics, as this will effect the maximum cycle rates for maximum use.
Anyway, as stated, this is how I judge lithium batteries.
A heads-up on my connection to lithium batteries.
I am “NOT” an expert on lithium batteries but I have been working with them for just over a decade now.
This included testing a large number of them and taking a couple of lithium batteries to the point where they were damaged, as requested by the supplier, so that they had a genuine idea of what their batteries could safely tolerate.
While I no longer sell lithium batteries, I still have a number of lithium batteries in my workshop, and I still carry out a fair amount of testing and I use these batteries as the Set-Point to compare with other lithium batteries.
From experience, so called “NAME” brands mean nothing, and neither does comparing Price vs Amp Hours. A common practice but falls short of anything meaningful.
The following is how I sort out good from not so good Lithium batteries and whether you follow this is completely up to you as the buyer.
First and foremost, get the specs for the battery. If there are no specs, or very limited specs, I personally avoid those batteries.
The specs need to include :-
“USABLE” Ah ( Amp Hours ) not just the total Ah.
Cycle rate to the lowest recommended DoD ( Depth of Discharge )
Optimum and maximum charge current.
Optimum and maximum “CONTINUOUS” discharge current.
Operating temperature range. While not as important as this should not be a problem in Australia but it is still a good idea to be sure the battery will be usable in RV conditions.
I also make sure the warranty period is no less than 3 years.
I have no intentions of using a lithium battery as a cranking battery, and nor do I intend to put one in an engine bay, and while this is a personal choice, it also governs where the battery is to be used.
My choice for seeing what value for money a given lithium battery is, is to compare Throughput to cost.
To do this, first get the cycle rate at the lowest DoD and multiply this by the amp hours at that DoD.
For instance, if a battery specs for a 100Ah lithium battery state that that particular battery can be cycled down to 80% DoD 2,000 time, then the Throughput for that battery 80 x 2,000, or 160,000 AMPERES.
If this battery cost $850, divide the 160,000 by 850 and you get the USABLE amperes per dollar, over the lifespan of the battery.
Here are some examples.
A Fusion V-LFP-12-100, a 100Ah Lithium battery can be cycles down to 100% DoD 1,600 times and with a cost of $998, this battery has a USABLE amperes per dollar value of 160.
A Solarking CB-100-12-100, another 100Ah Lithium battery can be cycles down to 100% DoD, 2,000 times and can be bought for $588, giving this battery has a USABLE amperes per dollar value of 340.
An Enerdrive EPL-100-12VLITE, another 100Ah Lithium battery can be cycles down to 80% DoD, 2,000 times and can be bought for $869, giving this battery has a USABLE amperes per dollar value of 178.
A Redarc LBAT12100, another 100Ah Lithium battery can be cycles down to 80% DoD, 2,000 times and can be bought for $1,498, giving this battery has a USABLE amperes per dollar value of 107.
Just beware, along with the USABLE amperes per dollar, you still have to consider maximum charge and maximum discharge characteristics, as this will effect the maximum cycle rates for maximum use.
Anyway, as stated, this is how I judge lithium batteries.