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Initial use of battery charger

I’m finding the charger settings somewhat unclear and vague. Some of the instructions for the BR2 battery reference “LiPo” even though the battery is designated as a Lithium-Ion (“Li-Io”). The settings are that different— does it matter whether the charger is set to LiPo or LiIo? When using the balanced charging, should the XT90 and the balance plug be connected? What is the two pin connector with blue wires for?

BR says you can charge it as a LiPo. I don’t, but you can if you want that extra tenth of a volt and a few extra mah.

Yes connect both the XT90 and the balance lead.

I thought the two pin was a temp sensor for chargers that have the ability to monitor, but I think those require three wires and that lead looks just like the ones for the water detect, so I’d guess it’s for detecting leaks in the battery bottle.

Thanks, Corndog. After it charged to the max voltage, the charger beeped as expected. Battery is charged and I feel a little more comfortable with the process. Thanks for your help!

Hi @Zissou and @corndog,

I’d like to clarify and correct a few points here. It is important to understand how to correctly use the battery and charger to maintain safety and the best performance, and it is critical that there is not conflicting information to confuse other users.

A note to all users reading this now and in the future:

Please note that all the information I am about to go over is present in the battery and/or charger documentation in the “Technical Details” and/or “Learn” tabs as relevant. It is very important to read all of the documentation on how to use the battery or charger before ever using them.

Some of the instructions for the BR2 battery reference “LiPo” even though the battery is designated as a Lithium-Ion (“Li-Io”). The settings are that different— does it matter whether the charger is set to LiPo or LiIo?

Our batteries are Li-ion, but they should be charged in Lipo mode. The reason for this is that they consist of modern lithium cobalt oxide cells that have the same maximum voltage as modern Lipo cells, 4.20 V. There is no difference charging our batteries versus a normal Lipo. Li-ion charge modes on most chargers are geared toward older Li-ion cell chemistries, which had a maximum voltage of only 4.10 V.

Since modern Lipo and Li-ion cells charge identically, a separate mode is unnecessary, and the older Li-ion mode is around for legacy reasons to charge older Li-ion cell chemistries. Charging our battery in Li-ion mode wont hurt anything, it just won’t give a full charge. You will miss about 500-800 mAh of charge by my estimate.

@corndog, the detailed information for the cells is present in the datasheet here. Samsung 30Q cells are fully designed and intended to be charged to 4.20 V/cell.

When using the balanced charging, should the XT90 and the balance plug be connected?

Yes. The XT90 discharge plug is used to charge the battery, and the balance port is used to selectively discharge the cells to get them to the same voltage as the a battery is charging.

Without the XT90 connector plugged in you will not be able to charge the battery, and without the balance connector plugged in, you will not be able to balance the battery.

What is the two pin connector with blue wires for?

The 2 pin JST-XH connector with blue wires is an NTC thermistor for measuring battery temperature. It has a β = 3435K, with R25 = 10kΩ, ±1% (at 25°C), and a working temperature of -40-110°C (-40-230°F).

-Adam