Can 12-Volt Battery Charger Charge Two 6-Volt Batteries Wired in Series

Updated 06/17/2020 | Published 02/21/2020

Products Featured in This Question

CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power

(98)

$199.99

NOCO Genius Smart Battery Charger - AC to DC - 6V/12V - 10 Amp

(164)

$99.95

Question:

If I connect two 6V batteries to get 12V, can I still charge only 1 battery with a 6V system? This is for having a 12V user on a 6V electrical charging system. Thanks!

asked by: Niels B

Expert Reply:

Being able to charge batteries wired in series isn't CTEK's strong suit. The # CTEK56353 charger will read the output as 12 volts, and could consider the batteries fully charged but it's possible they wouldn't be balanced. In this instance, CTEK recommends using a charger for 6V batteries, like part # CTEK56191 to charge the batteries individually. The batteries should be disconnected from each other for charging.

The NOCO chargers however, like # 329-GENIUS10 is capable of charging your wired in series 6V batteries in 12 volt mode, and will keep both batteries balanced.

expert reply by: Mike L

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Brett

6/13/2020

Can the Noco Genius10 de-sulfate 2 12-volt batteries connected in parallel?

Chris R.

6/17/2020

The NOCO # 329-GENIUS10 could de-sulfate your batteries but especially for this kind of charging/repair you would want to hook it up to each battery individually. I think a better option is the NOCO # NOC24FR, which features a 2-bank setup so you can hook both batteries up at the same time.