Brand new battery will not hold the charge after starting the vehicle with jumper cables - it dies and the battery is dead again.

2 cars, which one died
never jumper cable backwards (Plus/minus) or boom , electronics blow to H3LL. sorry if happened.
or
if car 1 battery is dead and will not crank. OR LOOSE RUSTY LUGS.
we jumper it with running 2nd car and noW car 1 cranks and runs.
BUT....?
now if cables are pulled (jump pair)
and car 1 dies, then car 1 battery or alternator is dead.
we test the battery first, we charge it and load test it (2 tools)

IF FAILS this test the BATTERY IS USELESS.
OR GET the BATTERY CAR 1 TESTING IN CAR STORE FOR FREE.
OK BATTERY GOOD BUT ALTERNATOR BAD.
NEW BATTERY STARTS THE CAR, AND IF ALTERNATOR IS GOOD
THE VOLTAGE ON THE BATTERY IS 13 TO 15VDC, BeLOW THAT , THE ALTERNATOR IS BAD. OR ITS FUSES are BLOWN.
OR BELT TO ALT IS LOOSE OR FELL OFF.

best is own a battery charger.
and if battery reaches, 12..6vdc rested it may be a good battery.

Once jumped n the jumper cables are removed it dies again. I would think it's not charging , alternator problem maybe .Is the battery light lit on the instrument cluster ?

1. Start the working vehicle.
2. Wait a minute or so. ...
3. Try starting the dead car. ...
4. If it doesnt start, you may need to let it CHARGE the dead battery for 10 minutes.
5. Keep the working vehicle running.
6. Once the dead car is running, you may disconnect the jumper cables, starting with the black, negative cable clamps. ...
7. Now, take a short drive.

I would suggest that you have a load test done on the existing battery as the indications are that it has several dead cells
the vehicle starts of the jumper battery but on removing the leads there is nothing with which to keep the ignition circuit operational
alternators need a current from the battery to start charging as they do not have residual magnetism in the stator so when you take the jumper leads off there is nothing to keep the alternator charging hence no power for the ignition circuit.

how can you have a brand new battery and no power...
fix this problem first

new batt if it is over 3 yrs old-needs to always be at 12.6 v--its not holding charge well--have it load tested--probly only gettn a surface charge onit-it will fool u

does the engine crank normally?? when you say it "attempts" to start?? how was the battery run dead??

This sounds like it is either a bad battery with a possible dead cell or a bad solenoid. If you haven't done so try jumping the vehicle by connecting ground to the engine block and disconnecting the positive cable from the battery and connect the positive jumper cable to the positive cable directly. If the vehicle starts then the battery has a dead cell. If it starts and dies when the cable is disconnected you ahve a faulty alternator or charging circuit.

Possible dead cell in battery, most likely a fault in the charging system. First, Jump Vehicle to get started then remove the Negative cable. If the vehicle dies when you take the jumper cables away or when you disconnect the negative cable your alternator or charging system is faulty. If the vehicle runs without battery connected you have a bad cell in your battery, replace the battery.

Your alternator is going bad. It should only put out 13-14 volts and therefore is overcharging your battery. This causes your battery to get a dead cell. If you replace the alternator and battery, make sure you check the cables for any shorts.