Lithium-ion (LiFePo) Batteries for Truck Campers

Joe Friday was a fictional character of the Los Angeles Police Department in the TV series Dragnet. Viewers quickly forgot the storylines; however, one line of his dialog was constant week after week:

“Just the facts, mam, just the facts. “

Thus, in keeping with Joe’s dialog when discussing truck campers’ choice/options of lithium-ion (LiFePo) or deep cycle lead-acid batteries (LA) –Justice scales “Just the facts.”

LiFePO batteries cannot

self-incinerate themselves.


Weight

Truck camper’s LiFePO batteries are typically 30% lighter (Battle Born LiFePO4 -31 lbs.  https://battlebornbatteries.com/shop/12v-lifepo4-deep-cycle-battery/) than LA batteries (Interstate Group 27 – 50 lbs.  https://www.interstatebatteries.com/recreation-vehicles/marine-batteries/deep-cycle).

LiFePO batteries can be mounted in any position or orientation, and there is no requirement for ventilation.


 Number of Cycles

The number of cycles for truck campers refers to the number of battery charges and discharges, with one cycle being counted as one time when you discharge a LiFePO to 80% of capacity or a LA to 50% capacity.

 LiFePO batteries can last an average of 3,000 to 5,000 cycles, while the average cycle for deep cycle LA batterie is 400 to 1,500 cycles.



Drawing showing battery charge

DISCHARGE

The discharge curve of LiFePO batteries is essentially flat, meaning that a LiFePO battery at 20% capacity will be providing nearly the same output voltage as it would at 80% with no reduction in lifespan or capacity. 

Recharging a LiFePO from fully discharged to fill recharge can be reached in typically only a few hours.

While the deep cycle LA batteries have a constantly sloping voltage discharge and will take at least a 50% loss in capacity and life expectancy when routinely discharged at more than 10% of capacity.

A LA can take a full day or more to be fully recharged and lose 50% of life expectancy if kept at partial charge states. 


Cost

Deep cycle LA batteries are less expensive than LiFePO batteries. Example: Interstate Deep Cycle Group 27 LA Battery, 80 Ah (amp hours), 12 volts, number of possible cycles not provided, cost per battery as of 5/15/20- $127.95.Chart showing cost vs value

Battle Born LiFePO Deep Cycle Battery – 100 Ah (amp hours), 12 volts with built-in BMS (Battery Management System), 3,000 – 5000 deep cycles, cost per battery as of 5/15/20 – $949.00.

Smart Battery’s Lithium Battery Deep Cycle Model SB100 – 108 Ah (amp hours https://www.lithiumion-batteries.com/products/product/12v-100ah-lithium-ion-battery.php), 12 volts with build-in BPS (Battery Protection System), 5000 deep cycles, cost per battery as of 5/21/19 – $1,249.99.

A LiFePO deep cycle battery has a much longer lifespan than a LA battery which helps offset the per-year cost.  However, it is still an expensive investment. 

Chart showing cost vs.speed
COST LEAD-ACID AGM GEL LITHO
Purchase Cost $185 $279 $400 $949
Number of Replacements * 14 20 7 0
Cost of Replacements * $2,590 $5,580 $2,800 $0
Cycles Over Life Time* 4200 8000 70000 7100
Life Time Cost Per Cycle 0.61 $0.69 $0.40 $0.13

RELiON Battery provided the chart above

https://relionbattery.com/blog/total-cost-ownership-lithium.

  • RELiON calculated the total cost of ownership of each battery over a single lifecycle of the RELiON LiFePO RB100 since it has the longest life of all four batteries. Each of the three lead-acid batteries requires multiple replacements over the life of one RB100. 
  • The table above shows each factor in the overall total cost of ownership for each battery and the total cost of each battery per cycle. Based on the specified lifetime of each battery and their retail prices.
  • The chart does not and should not be considered an endorsement of RELiON batteries by Northeast-Truckcampers.org.

Charging of a Truck Camper Battery

Chart showing % of battery charge
State of Charge for a LiFePO

When charging a LA battery, you can lose between 15-30% of the energy from your charging unit to the battery due to heat loss.  LiFePO batteries are 99% efficient and will accept nearly 100% of the power from your charger or solar panel(s).

LiFePO batteries have 10 times faster recharging in as little as 1 hour from a completely dead battery.  This circuity is custom-made for the battery, thus increases its already expensive cost. If you have a 100 AH LA battery and a 100-amp charger, it will take longer to charge fully. Yet this type of battery cannot handle being over-voltage or overcharged.


Notice – Warning – Consideration

Consider this a notice, warning, or any other description you may want to call it by – the purpose is to inform you before making your purchase of a LiFePO battery and not discourage you.   

Your solar controller is an essential component of your solar system.  The controller maintains the life of the battery or batteries by protecting your investment from overcharging.  When your battery has reached a 100% state of charge, the controller prevents overcharging by limiting the current flowing into the batteries from the solar array.

BEFORE purchasing LiFePO batteries, ensure that your solar controller can support batteries that are equipped with a Battery Management System or a Battery Protection System.  If not, you may want to consider purchasing a controller that can support and protect your new investment.

Also, ensure that your onboard shore power converter can support LiFePO batteries. Another purchase you may have to consider.


Any suggestions, comments – good or bad – please contact us at

webmaster@northeast-truckcampers.org. Thank you.