Frequently Asked Questions

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If your charger offers a LiFePO4 setting, we recommend selecting it. For example, Victron DCDC and MPPT chargers have a LiFePO4 setting available; please choose this option.

Recommended 12v charging parameters are as follows:

Bulk Charge: 14.2V – 14.6V (ideal: 14.4V)

Absorption: 14.2V – 14.6V (ideal: 14.4V)

Float: 13.4V – 13.6V (ideal: 13.5V)

Recommended 24V charging parameters are as follows:

Bulk Charge: 28.4V – 29.2V (ideal: 28.8V)
Absorption: 28.4V – 29.2V (ideal: 28.8V)
Float: 26.8V – 27.2V (ideal: 27.0V)

Lithium batteries are eager to charge, typically accepting high charging rates until they reach around 98% capacity, after which absorption slows down.

It's recommended to charge lithium batteries at a rate of half the amp-hour (AH) rating of the battery, provided this is within the limits of the battery's BMS (Battery Management System) amp rating so for example a 310AH battery is recommended to be charged at 155 Amps.

When choosing between smaller and larger models of DC-DC chargers, the decision hinges on desired charging speed and the capacity of your alternator to meet the demand while ensuring the cranking battery remains adequately charged, especially during shorter trips around town. For larger lithium batteries, opting for a larger DC-DC charger is advisable as it can recharge the battery more efficiently, maximizing charge levels before parking. However, using a smaller charger is also feasible and not problematic.

In summary, lithium batteries benefit from high charging rates but should adhere to recommended charging guidelines based on the manufacturers ratings and BMS limits.

Choosing the appropriate size of DC-DC charger depends on your specific charging needs and the capabilities of your vehicle's electrical system and the battery.

 Yes, it is perfectly fine to use multiple chargers simultaneously to charge your battery bank. 

For example, you can charge from solar panels on the roof of your caravan while driving, and also use a DC-DC charger.

When parked, you can use shore power and solar panels for additional charging. 

 Contrary to the myth, the chargers will not "fight" each other. 

No.

A DC-DC charger is designed to handle the specific charging requirements of lithium batteries. This ensures that your lithium batteries receive the correct voltage and current for optimal performance and longevity.

Charging directly from the alternator can lead to several issues:

Overvoltage Risk: A regulator failure might cause excessive voltage, potentially damaging your batteries.

Undercharging: Long wiring runs can result in insufficient charging of your auxiliary battery due to voltage drop.

Reduced Battery Life:  Alternators typically operate around 14.4V. Holding the battery at this level for extended periods, such as during hours of continuous driving when the battery is fully charged, can shorten its lifespan.

There is also the potential that your wet cell starting battery may be starved of current while driving. This can happen in a manner similar to running a DC-DC charger that is too large for your alternator to sustain, which can also affect the charging of your starting battery.

Additionally, the alternator may exceed the BMS (Battery Management System) rating, potentially causing damage and reducing battery performance. 

No, LiFeTek batteries can not be connected in series this can damage the BMS.

For 24v or 48v applications it is also recommended to use a 24V or 48V battery instead of running 12V batteries in series. 

Low voltage disconnection in series can cause a break in the circuit, leaving the charging system unable to revive the battery bank. This occurs because one battery becomes isolated and requires individual jump-starting at 12V.

Yes, it is important to ensure that they are fully charged before connecting, and that there is no more than a 0.2V difference between them after resting for an hour. This prevents high current from transferring from one battery to another, which could potentially cause damage to the BMS or trigger the BMS to shut down.

We recommend using no more than 4 batteries in parallel and opting for a larger battery instead of paralleling multiple smaller batteries to create a large bank. For example, choosing one 620Ah battery over two 310Ah batteries, or selecting two 620Ah batteries over four 310Ah batteries.

When using two or more batteries, we recommend to avoid discharging the battery bank down to 10V BMS shut down.

To prevent this, use a low voltage protection device on your loads and configure your inverter to shut off above 10V (typically around 11.5V). Alternatively, ensure that the battery does not drop below 11.5V or around 5% state of charge (SOC) 

It is also advisable to fuse between each battery for added circuit protection.

Due to potential uneven current sharing when paralleling batteries, it is advisable to limit the load to no more than 75% of the combined BMS ratings. For instance, if two batteries each have a 300A BMS, the total load should not exceed 450 amps across both batteries.

Ensure that heavy-gauge wiring is used, with the shortest possible lengths connecting the batteries. 

The inverter should have a low voltage cutoff set above the batteries' 10V low voltage shutdown threshold, recommended 11.5v shut down for inverters.

Refer to the diagram at the bottom of the page for proper wiring of batteries in parallel to ensure even current sharing.

We do not recommend connecting batteries in parallel if they have different BMS amp ratings or use different brands of BMS.

This advice is specific to LiFeTek batteries. Consult your manufacturer, as not all batteries are the same.

When swapping AGM batteries with lithium batteries, it's crucial to verify that your existing chargers and equipment manuals support lithium battery charging requirements. Equipment such as your DC-DC charger, solar charge controller, and 240V charger should be checked for compatibility with lithium batteries.

AGM and lithium batteries operate on different charging voltages, and their voltage triggers in charging profiles also differ. Lithium batteries require specific charging profiles to avoid triggering BMS protections and to ensure effective charging.

Some AGM chargers may initially charge lithium batteries, but issues can arise during the transition from float mode back to bulk charge. In lithium profiles, this transition typically occurs around 13.2V, whereas for AGM batteries, it's around 12.6V. Consequently, the lithium battery may charge fully in the first cycle and then drop to float, but the charger might allow the battery to drain almost flat before initiating bulk charge again. This discrepancy can go unnoticed with vehicle DC-DC chargers, as they are manually cycled with vehicle start-stop. However, for shore power and solar charging, this may lead to reduced yield and ineffective battery charging.

Another concern is older AGM chargers with desulfation maintenance modes that pulse higher voltages. These higher voltages can trigger the BMS to shut down or potentially damage it.

Therefore, it's essential to thoroughly review your equipment manuals to confirm lithium battery compatibility. Ensuring compatibility will help optimize performance and longevity while preventing potential damage to your lithium battery setup.

In short, yes.

Cell manufacturers rate cycle life based on the level of discharge. For example, a battery might be rated for 3,000 cycles at an 80% discharge level. If you cycle the battery daily—discharging it to 20% and fully recharging it—it would take approximately 8.2 years to complete 3,000 cycles before the battery is considered at the end of its service life, degrading to 80% of its original capacity while still remaining operational for some time afterward.

Using 100% of the capacity occasionally will not significantly shorten the battery's lifespan. Even doing so every day, you can still expect approximately 2,500 cycles or around 6.8 years of service life.

If you find yourself in a situation where there has been little solar input while traveling, and your battery is low, you can use the remaining capacity to keep essentials like lights and the fridge running until you have access to more solar power or shore power. 

Don’t worry about using the remaining capacity; it won’t have a dramatic impact on the battery’s longevity.

When using two or more batteries in parallel, we recommend to avoid discharging the battery bank 100%  To prevent this, either use a low voltage protection feature on your loads or configure your inverter to shut off above 10V (typically around 11.5V). Alternatively, ensure that the battery does not drop below 11.5V or around 5% state of charge (SOC) 

Our BMS will shut down at 10v, but we recommend setting your low voltage cutoff to 11.5 volts for your equipment.

For long-term storage of 3 months or more, it is advisable to store the battery at a 50% state of charge and isolate it from your system to prevent potential parasitic drain. 

LiFePO4 batteries have a self-discharge rate of around 3% per month, so it's important to check the battery every few months to ensure ideally it does not drop below 12V or worse 10v for an extended period of time, which can damage the cells.

If storing your van with solar charging active and running a fridge, it is acceptable for the battery to lightly cycle long-term while your van is not in use, spending the majority of its time fully charged on float.

If you do not have a battery shunt monitor to measure battery percentage, then store the battery isolated at around 13.1-13.2V resting. 

 The simplest method requires only a lithium-compatible 240V charger, like a Victron, which can apply a charge even if it doesn't detect a battery, or a charger with a 'power supply' mode to wake up the battery.

Connect the battery to the 240V charger with the mode set to 'power supply' and allow it to charge. Some chargers may automatically detect and initiate charging for sleeping lithium batteries, while others may require voltage sensing before starting.

It's recommended to fully charge the battery after performing a flat reset.

Portable jumper packs often output a higher voltage than LiFePO4 batteries typically operate at, as they often use Lithium Polymer cells with higher voltage ranges. This voltage discrepancy can trigger the BMS to shut down immediately due to high voltage protection during jump starts or wake-up procedures. If this occurs and the battery does not wake up, try using an older lead-acid jump pack or a different charger 

Alternatively, another method to revive a flat lithium battery without a 240V charger is to apply 12V from another battery using jumper leads. Please ensure correct polarity connections to avoid damaging the BMS.

If your battery has been left completely discharged for an extended period and these methods do not work, please contact LifeTek for assistance in diagnosing whether the battery can be revived or if it has degraded beyond functionality.

In the event of a short circuit, the BMS will shut down in the attempt to protect the battery.

To reactivate the BMS, follow these steps:

Firstly, rectify the short circuit.

Secondly, remove all loads from the battery and isolate it by disconnecting it from your system.

Allow approximately 5 minutes for the BMS to restart.

If the battery fails to restart and function, it may indicate damage to the BMS. Please contact LifeTek for support. 

 Our VanLiFe range of batteries can be mounted on their base, side, and back, but they cannot be mounted upside down or with the terminals facing downward towards the floor.

 A 1/2” BSP fitting is provided for easy attachment to vent to the exterior of your van. Standard brass plumbing fittings and copper pipe are readily available at Bunnings or plumbing stores. Alternatively, you can attach a hose barb and use silicone hose with a one-way valve or filter.

We recommend routing the vent to a location that is unlikely to encounter water ingress, similar to how a differential breather is installed. If there is potential for water to enter the vent we strongly recommend using a 1/2" one way check valve typically available for around $8

Regarding dust, the sealed battery box typically prevents dust ingress since the internal air cannot be purged. However, we recommend using at least a filter to prevent ants and potential contaminants from entering.

When installing your fitting onto the vent outlet, use a spanner to hold the outlet steady and prevent it from spinning while you screw the fitting onto it. 

Yes, the cells used in constructing our high-quality lithium batteries are certified to IEC by TÜV Rheinland