[Al Skierkiewicz]

OK,
Let's get some info straight here and in one place.
1. Our batteries are specified by the manufacturer to be charged at 6 amps or less. Battery life can be significantly increased when charged at 1/10 C or about 2 amps.
2. Life is significantly reduced by heavy loads like an FRC robot drawing currents in excess of 200 amps over a two minute match.
3. Charging at high current on our batteries causes internal heating and the possibility of out-gassing and case failure if the vents do not operate.
4. Our batteries are AGM types and the plates within the cells are not as robust as older technology lead-acid batteries.
5. Excessive heat within the battery causes the plates to deform, leading to internal shorts and a variety of other issues leading to lower battery life.
6. Hot batteries during charge can fool many/most smart chargers into producing damaging voltage/current during the charge cycle.
7. AGM batteries are nothing like NiMH, NiCd, LiPO, Li ION or other types and each requires a specific type of charger. Do not mix chargers and battery types.

Now on to the problem...
You can use a larger battery, the marine type for example. It must be a 12 volt battery of course. The motor heating encountered should be relatively the same with any size battery you choose. If you are interested more in practice then in demo, I would suggest that you stick with the FRC robot batteries for a variety of reasons. One is that the larger battery will be much heavier and while practicing, you will be over compensating for the added weight. Also, the larger battery will be able to better supply current to your motors giving you performance that will not exist in competition. If your robot draws a lot of current then the larger battery will also lure you into a false confidence that the battery will continue to supply enough voltage to prevent the systems from shutting down. Remember that the Crio monitors the battery voltage and inhibits all output when the battery falls below 5.5 volts at terminal voltage. The regulated supplies in the PD fail at about 4.5 volts which cause both Crio and radio reboots. If you want real world practice you need to keep real world conditions.