charged first. It's been a while since I tested with standard 9v but I recall it was about 6 hours.
They're NIMH batteries! They JUST need cycled a handful of times, so they get to their maximum capacity
After about 5-6 cycles, they'll be putting out 230+mah, trust me
If you want them to charge up to their maximum capacity WITHOUT cycling them a handful of times, if your charger allows, DISCHARGE the 9v batteries@8.4v[Nominal Voltage], but ONLY at .1a/100mah. Then CHARGE them @8.4v/.1a[8.4v/100mah]. I ALMOST GUARANTEE that they will charge up to their max cap of 230mah after discharging/charging them that slowly! That's essentially a "Break IN" charge and does the job damn near everytime. It should ALWAYS be done on NEW/Worn Out batteries
I have been studying batteries since the early 2000's, and I am CONSTANTLY charging/discharging batteries of all kinds[NIMH/Li-Ion most often], and I KNOW my batteries
Plus, I JUST spoke with someone very knowledgeable at "Tenergy" Battery Company and he reminded me some of this stuff, since it's been awhile since I researched it
This is quoted from someone at Tenergy
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dear Bean,
It is best to charge both batteries at the nominal voltage. For the 9V battery, you would set the charger for 8.4V or use the automatic feature for NiMh batteries. This should give the battery a voltage between 10.5V-11.V. The recommended charge rate and discharge for this battery is 100mAh or .1A, please do not exceed this rate.
The 9.6V battery pack should also be set to 9.6V at a 1A rate. The rapid rate is 2A but we don't recommend using this rate too often.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
And about charging 9v/Li-Ion batteries.............
Dear Bean,
For the Li-ion batteries, they operate at 7.4V. You should set the TB6B 7.4V (2s) at .1a.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
So for ALL 9v Rechargeables, charge them at NO MORE than .1a[100mah], whether they're NIMH or LI-Ion[if your charger allows obviously]!!! It will GREATLY extend their life and they will have a greater capacity as well!