Basics of Lithium conversion... I'm lost!
I did a search and it's mostly Greek... to me. I'd like to know the key points for, hopefully, a straight across lead/acid to lithium conversion. My old Flow-Rite watering system just overflowed 2 c...
Forum Discussion
For best life span take no lower than 40% state of charge, do not charge to more than 90%
This is a truism - for any and all batteries the less you use them the longer they last. However for lithium you can use them from 100% - 0% SOC 2000 - 3000 times, which is far more cycles that 99% of RVers will ever use and is far better than any alternative - thus they are less fussy than lead acid in this regard.
do not float charge, store at 50% state of charge, do not charge below -4 f, have a dc to DC charger to protect the alternator,
There is no need to float charge (less fussy than lead), there is an ever so slight advantage to storing near 50% SOC, but this far less important than storing lead acid at 100% SOC (again less fussy than lead acid). The cold weather charging is a legit concern, unless you have a dumb alternator connected with a really short fat wire, the requirement for a DC-DC charger is also not true.
have a good battery management system, do not use above 140 f (irrc), do not draw power at greater than 0.5 C (not for all makes), have a high voltage (14.8 volts) source available to "reset" the battery management system if it "shuts down" the battery
Assuming we are talking about drop ins, then the BMS is included, the user doesn't have to do anything, there is no need for a 'high voltage source' BMS low voltage disconnect will reset at normal charge voltages, most drop in's will discharge at 1C with far less Peukert issues and voltage drop than lead (again less fussy). High temperature use will shorten their lifetime, but again this is not specific to lithium and is true of any battery.
Charge to 100% to rebalance the cells every so often, do not discharge to 0 soc, do not use temperature compensation charging, do not wire in series and initial cost is quite ridiculous unless you roll your own.
Depending on how the BMS is configures you may or may not need to charge to 100% to balance the cells, but in any case this is requires less often than lead requires it to avoid sulfanation (less fussy). You can discharge to 0% SOC somewhere in the range of 2-3000 times (less fussy), you don't need temperature compensated charging (less fussy) but as long as your max voltage is range it won't hurt. With most lithium batteries you can wire in series, but in general there is no need as lithium is available in 24 or 48V batteries if that is your desire (less fussy).
Yes they are more expensive upfront than generic lead acid, but they are significantly cheaper over their lifetime and the prices are falling fast. The upfront costs are also now about the same as your vaunted SiO2 (and way cheaper over time).
This is a truism - for any and all batteries the less you use them the longer they last. However for lithium you can use them from 100% - 0% SOC 2000 - 3000 times, which is far more cycles that 99% of RVers will ever use and is far better than any alternative - thus they are less fussy than lead acid in this regard.
do not float charge, store at 50% state of charge, do not charge below -4 f, have a dc to DC charger to protect the alternator,
There is no need to float charge (less fussy than lead), there is an ever so slight advantage to storing near 50% SOC, but this far less important than storing lead acid at 100% SOC (again less fussy than lead acid). The cold weather charging is a legit concern, unless you have a dumb alternator connected with a really short fat wire, the requirement for a DC-DC charger is also not true.
have a good battery management system, do not use above 140 f (irrc), do not draw power at greater than 0.5 C (not for all makes), have a high voltage (14.8 volts) source available to "reset" the battery management system if it "shuts down" the battery
Assuming we are talking about drop ins, then the BMS is included, the user doesn't have to do anything, there is no need for a 'high voltage source' BMS low voltage disconnect will reset at normal charge voltages, most drop in's will discharge at 1C with far less Peukert issues and voltage drop than lead (again less fussy). High temperature use will shorten their lifetime, but again this is not specific to lithium and is true of any battery.
Charge to 100% to rebalance the cells every so often, do not discharge to 0 soc, do not use temperature compensation charging, do not wire in series and initial cost is quite ridiculous unless you roll your own.
Depending on how the BMS is configures you may or may not need to charge to 100% to balance the cells, but in any case this is requires less often than lead requires it to avoid sulfanation (less fussy). You can discharge to 0% SOC somewhere in the range of 2-3000 times (less fussy), you don't need temperature compensated charging (less fussy) but as long as your max voltage is range it won't hurt. With most lithium batteries you can wire in series, but in general there is no need as lithium is available in 24 or 48V batteries if that is your desire (less fussy).
Yes they are more expensive upfront than generic lead acid, but they are significantly cheaper over their lifetime and the prices are falling fast. The upfront costs are also now about the same as your vaunted SiO2 (and way cheaper over time).
