When connecting or charging batteries in series your goal is to increase the output of your batteries nominal voltage rating. The basic concept when connecting in series is that you add the voltages of the batteries together but the amp hour capacity remains the same.
Designing Charging Circuit Rechargeable Battery Seiko
Charging batteries in series. Case each charger connects to one battery. When you charge batteries in series you are charging the entire group of them all at the same time. You need to overcome the total voltage of the series batteries 12 v 12 v 24 v to drive electrons. When you charge in series you connect the negative terminal of the first battery to the positive terminal of the second battery then connect the charger positive terminal to the first battery positive terminal and the charger negative terminal to the negative terminal of the second battery. Some packs may consist of a combination of series and parallel connections. If the batteries are not each at the same voltage this means that one battery is charging higher than the rest and one is not charging as high as the rest.
Thats the pat answer. Such a configuration is called 4s2p meaning four cells in series and two in parallel. It is normal to charge lead acid batteries in series. For example you can connect two 6v batteries in series with a 12v source to recharge them. Charging batteries in series increases the voltage across each battery. One basic configuration for charging batteries in series is to connect the positive charger output in red to the positive end of one of the batteries.
Then connect the negative end of the battery to the positive end of the next one and continue to do so for the rest of your batteries. If they were charged in parallel the one with the high voltage wouldnt get much current and the one with the low voltage would get too much current. Laptop batteries commonly have four 36v li ion cells in series to achieve a nominal voltage 144v and two in parallel to boost the capacity from 2400mah to 4800mah. To do this you need to connect the pos terminal of the first battery to the neg terminal of the second battery. As they are used the cell voltages will change which is why they are not charged in parallel. For the final battery connect the negative end of the battery to the negative output in black of the charger.
As in the diagram above two 6 volt 45 ah batteries wired in series are capable of providing 12 volts 6 volts 6 volts and 45 amp hours. The charger will stop charging when the entire group reaches a certain voltage. The voltages themselves should add together to equal the voltage of the battery pack source. To charge two 12 volt batteries in series youd need a 24 volt charger.


















