Joe Friday was a fictional character of the Los Angeles Police Department in the TV series Dragnet. The storylines weeks after weeks were quickly forgotten however, one line of his dialog was constant week after week:
“Just the facts ma’am, just the facts “.
Thus, in keeping with Joe’s dialog when discussing truck campers options for batteries – deep cycle lead-acid, sealed absorbed glass mat (AGM), lithium-ion
“Just the facts”.
Weight
Truck camper’s lithium-ion batteries are typically 30% lighter (Battle Born LiFePO4 -31lbs) https://battlebornbatteries.com/shop/12v-lifepo4-deep-cycle-battery/) than deep cycle lead-acid batteries (Interstate Group 27 – 50 lbs) https://www.interstatebatteries.com/recreation-vehicles/marine-batteries/deep-cycle or a sealed absorbed glass mat battery (AGM) (Optima Blue Top D31M – 59.8 lbs) https://www.optimabatteries.com/en-us/bluetop-dual-purpose-deep-cycle-and-starting/d31m .
Battery Cycles
Important to truck campers – battery cycles. The number of cycles refers to the number of charges and discharges, with one cycle being a full discharge of a fully charged battery. The average cycle for deep-cycle lead-acid and sealed absorbed glass mat batteries is 400 to 1,500 cycles. Lithium-ion batteries can last an average of 3,000 to 5,000 cycles
DISCHARGE
Deep-cycle lead-acid batteries exhibit a continuously sloping discharge voltage. Lead-acid and AGM batteries have a shelf life. As a general rule, the less you discharge your battery, the longer it will last.
If your battery is rated for 3000 cycles and is discharged by a third each day, you have 8 years of service (just an estimate). Should the discharge be by a quarter, you get 9 years of service. If you don’t discharge at all, you get 10 years.
The discharge curve of lithium batteries is essentially flat, meaning that a lithium battery at 20% will provide nearly the same output voltage as at 80%.
Cost
Truck camper deep-cycle lead-acid batteries are less expensive than AGM or Lithium-ion batteries. Example: Interstate Deep Cycle Group 27 Battery, 80 Ah (amp hours), 12 volts, number of deep cycles not provided, cost per battery as of 5/15/20- $127.95.
A Duralast Platinum AGM battery – Group 25 – with 550 cold-cranking amps (685 cranking amps) – 12 volts – Amp-hours and number of deep cycles not provided – cost as of 8/27/20 – $199.99.
Battle Born LiFePO4 (Lithium-ion) 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 9/26/20 – $949.00.
Truck Camper Battery Charging
When charging a lead-acid battery, you can lose 15-30% of the energy from your charging unit to heat loss.
Charging an AGM is best when it is low and slow. A low-amp charger (1 to 12 amps) is generally the best choice for charging any lead-acid battery. It’s quicker to charge at a higher amperage, but it can also generate a lot of heat, which reduces a battery’s life, just like the heat of summer.
Webmaster’s comment – The table below was provided by RELiON, a manufacturer of Lithium-ion batteries. Thus, the figures may seem one-sided, biased, and prejudiced to say the least.
Lithium-ion batteries are 99% efficient and will accept nearly 100% of the power from your charger or solar panel(s). The batteries have a 10 times faster recharging time, in as little as 1 hour, from a completely dead battery. This circuit is custom-made for the battery, thus increasing its already expensive cost. If you have a 100 AH lead-acid battery and a 100-amp charger, it will take 1 hour to fully charge. Yet this type of battery cannot handle overvoltage, overcharging, or discharge. One company, Battle Born LiFePO4 (Lithium-ion) Deep Cycle Battery, offers a BMS (Battery Management System) for protection. Another manufacturer, Smart Battery (http://smartbattery.com), features an automatic, built-in battery protection system (BPS) that keeps the battery running at peak performance and prevents overcharging.
Any suggestions, comments – good or bad – please contact us at
webmaster@northeast-truckcampers.org. Thank you.