LiFePO4 batteries: Suitable car chargers & settings
Find out in our article why normal car chargers with a gel characteristic are ideal for charging LiFePO4 batteries. We have also compiled a list of suitable chargers and the correct settings to ensure safe and optimum battery performance.
Why (most) normal chargers and EBLs are also suitable
Most lithium battery manufacturers state that lithium batteries should be charged with a CC/CV characteristic. In writing, this means Constant Current and Constant Voltage, i.e. constant voltage and constant current.
If we look at the vast majority of standard chargers installed in motorhomes, these devices have an IUoU characteristic curve for AGM/GEL/acid batteries.
The IUoU charging characteristic is a multi-stage charging method that is often used for lead-acid batteries, but can also be used for lithium batteries if configured correctly. The IU0U characteristic curve consists of the following phases:
I phase (current limitation): In this phase, the battery is charged with a constant current (CC). The charging current should be within the specifications of your lithium battery.
U-phase (voltage limitation): After reaching a certain voltage threshold, the charger switches to constant voltage mode (CV). The voltage is kept at a constant value that does not exceed the recommended charging voltage value for your lithium battery. The charging current gradually decreases as the battery continues to charge.
0U phase (trickle charge): As soon as the charging current falls below a certain threshold value, the charger switches to the trickle charge phase. In this phase, the battery is kept at a lower voltage to keep it fully charged and ready for operation.
Make sure that your charger supplies the correct charging voltages and currents for your specific battery. Observe the manufacturer’s specifications for the recommended charging voltages and charging currents for your battery to ensure the service life and safety of your lithium battery.
Example: Schaudt EBL 30
We can see that the decisive factor is not so much the characteristic curve (IU and CCCV are the same thing), but rather the adaptability of the parameters:
- Charging voltage
- Charging current
- Float voltage
However, we explain below why this is already the case in most cases, using the EBL 30 from Schaudt as an example:
The Schaudt EBL initially charges in phase 1 with constant current (18A) CC.
As soon as a certain threshold value is reached, the charger switches to the full charge phase “U” or “CV” and charges until the final charge voltage of 14.4V for lead gel or 14.7V for AGM has been reached, or the 16h for gel or 4h for AGM has been reached.
The device then switches to the trickle phase. A voltage of 13.7V is applied here to prevent the battery from discharging.
The parameters of the Schaudt EBL are summarized once again:
- Characteristic curve: IUoU
- Charging voltage: 14.4V
- Charging current: 18A
- Float voltage:13.7V
Recommended charging parameters Supervolt LiFePO4
Now let’s see if these values match our batteries.
The recommended values for our batteries are as follows:
- Characteristic curve CCCV/IU
- Recommended charging voltage 14.2 V – 14.6 V
- Maximum charging voltage: 15.2V
- Float voltage 13.5V – 13.8V
- Maximum charging current: 100A
Comparison of Schaudt EBL and Supervolt battery parameters
| Value | EBL30 | Supervolt 100Ah |
| Characteristic curve | IUoU | CCCV |
| Charging voltage | GEL 14.4V | AGM 14.7V | 14.2-14.6V | 15.2V max. |
| Float voltage | GEl 13.7V | AGM 13.7V | 13.5V – 13.8V |
| Charging current | 18A | up to 100A |
We can see that our Supervolt 100ah LiFePO4 can be charged by the Schaudt EBL without any restrictions. The values of the EBL are within the specification range of our batteries.
Exceptions: Which devices are not suitable?
Most chargers with multi-stage charging processes, such as the chargers from CTEK, are not suitable. In particular, most chargers with an integrated desulphation function are unsuitable as the voltage is too high.
Also, batteries that do not have a BMS must not be charged under any circumstances.
Batteries with BMS block the charge in the event of overvoltage, overcharging, too high or too low a temperature. LiFePO4 batteries without BMS are damaged or, in the worst case, start to inflate and release the excess pressure with heat and smoke.
List of suitable chargers for LiFePO4
Below is a comprehensive list of the standard chargers installed in most motorhomes and their correct settings for our Supervolt batteries. Batteries from other manufacturers have different requirements and may not be compatible.
| Device designation | Setting |
|---|---|
| 1230CED, 1240CED |  |
| alden sps220 |  |
| Büttner MT MPP-260 |  |
| CB516 |
GEL setting under housing
|
| CB520 | Setting B |
| Dometic MC 1215 | S1 ON S2 OFF S3 OFF S4 Energy saving setting |
| Dometic MCA 1225 | S1 on S2 off S3 Off S4 on |
| Dometic Perfect Charge CA360 |  |
| Dometic Perfect Charge IU4512 | S1 ON S2 OFF S3 Off S4 Off |
| EVS 17/16-DS/IU | AGM / gel battery setting |
| Company Calira EVS 30/20-DS/IU | GEL setting |
| Charging booster DCC 1212-20 | S1 ON S2 ON S3 ON S4 ON S5 OFF S6 ON |
| Model NE287 17A | OFF OFF IUoU-GEL curve |
| Mpp-440 | |
| NE186 |  |
| NE325 | LiFePO4: S1: OFF, S2: ON |
| NORDELETTRONICA Charger Mod.Ne 143 | GEL 14,4V |
| NORDELETTRONICA Ne 297 21A | OFF OFF |
| PerfectCharge SMP439A | Gel |
| Redarc BCDC1240 | GEL/AGM |
| Schaudt CSV409 | GEL 14.4V |
| Schaudt EBL 99, EBL109, EBL119, EBL 31, EBL30 | gel |
| Solar controller Vechline 3906 | Lithium |
| Sterling B2B, BBC2412, 30A |  |
| Sterling Pro Charge D 12V | |
| VCC 1212-30 |  |
| VOTRONIC solar controller MPP 250 Duo Dig |  |
