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All set for spring and summer!


So you have a camper bus, motor home or caravan and the big freeze is finally over. Banner now gives you valuable tips on how to best wake your vehicle and battery up from the sleep of winter. Camping vehicles that have not been used during the winter months and have been in hibernation either outside or indoors will be ready to head off on the first trip in spring. If your vehicle has not been used or has been decommissioned for a longer period of time (standing or hibernation time), it is essential to check your starter and electrical system battery. This is usually done using AGM technology. 

Ensure your starter and electrical system battery have a long service life with AGM technology


It’s essential that you check the open-circuit voltage with a battery tester or voltmeter. Please make sure to recharge the battery as soon as an off-load voltage limit of approx. 12.5V has been reached. To be able to measure the open-circuit voltage with a testing device, you should wait for approx. five hours after the battery has been completely charged, or at least one hour without discharging.

An AGM battery should only be discharged to a maximum of 50% of its charge level.

In general, the deeper the discharge, the shorter the lifetime expectancy. An AGM battery can achieve up to 400 cycles at a discharge depth of 50% (approx. 12.3V open-circuit voltage).

Banner’s charging tips for AGM batteries


  • Only use direct current to charge the batteries.
  • If the battery is disconnected or removed: Connect the positive terminal (+) of the battery to the (+) terminal of the charger and the negative terminal (-) to the (-) terminal of the charger.
  • If the battery is connected or installed: Connect the positive terminal (+) of the battery to the (+) terminal of the charger and the negative terminal (-) of the charger to earth (= unpainted body, bare metal).
  • Do not switch on the charger until the battery has been connected. When the battery has finished charging, first switch off the charger.
  • We recommend a charging current of approx. one-tenth of the capacity (e.g. 60Ah: 10 = 6A charging current). With automatic chargers like the Banner Accucharger, this setting is performed automatically.
  • If a temperature of +55°C is exceeded, you must stop charging the battery.
  • Ensure good ventilation when charging.
  • The screws on the AGM batteries may not be opened! It’s not possible or necessary to measure the acid density or refill with distilled water!
  • Please note that 1.2 times the removed capacity must be recharged. (e.g.: Removed capacity 30 Ah --> recharging 36 Ah!)
  • The battery is fully charged when the current drops to 0 or no longer decreases or the automatic charger switches itself off.

Caution: An explosive oxygen-hydrogen mix can form during charging. Fire, sparks, naked flames and smoking are prohibited.

Which charging device is required?


As a general rule, fully automatic chargers (charging voltage limitation with 14.8V) are well suited for charging the battery installed in a vehicle. These charging devices run fully automatically. Depending on the capacity of the battery, you can use the following chargers and all come with a charge retention function:


If you already have a charger, please take note of the following information:

Use the AGM setting, the charging voltage should be max. 14.8V and the retention charging voltage should be set to 13.5V. It would be best to use an IUoU characteristic with temperature compensation (if you have the option of adjusting it).


We also recommend the battery tester so that you can periodically check the battery voltage. BBT DBA - Digital Battery Analyser

Follow these hot tips to guarantee you have a successful new travel season without an unscheduled pit stop for you and your battery-powered vehicle. Because next summer is definitely on its way.