george10, la 19 Jan 2008, 11:52, a spus:
fulgerica, la 19 Jan 2008, 01:17, a spus:
HESS, la 19 Jan 2008, 00:36, a spus:
Nu poti pune un PB de 12V/55A pe un model de 2Kg, ca sa te dai 10ore... Vei pune unul de 4A si te vei da 30min :lol:
chiar si teoretic acumulatorii de masina nu pot fi folositi pt asa ceva. daca l-ai descarcat sub 80% din capacitate il poti arunca dupa aceea. unul de 55A tine cel mult dublu cat cel de 4A, max 1 ora.
Ce as mai vrea sa te contrazic in practica nene "fulgerica"
Tu ai vazut ce ai scris? :lol: De unde le scoti?
Cu stima George
tati, descarca tu o baterie pb acid sub 80% din capacitate si vezi la cat se mai incarca dupa aceea.
daca e vorba de baterii cu ciclu adanc de descarcare, cu gel, e alta poveste.
oricum, puteai gasi pe net o gramada de linkuri care-ti explica care-i treaba cu ciclul de descarcare al unui acumulator pb-acid.
cat despre calcule, vezi ce inseamna 20% din 55A.
uite cateva (ti-am extras textele exemplicative):
The general guidelines throughout the Pb-acid battery industry is to not discharge below 80% of capacity for regularly used batteries, such as fork trucks, which is less severe service than we use for ALVIN. The net result is that ALVIN leaves the bottom with only 10% of the "usable" battery left to get to the surface, maneuver if required, and get secured in the hanger until external power is connected. Our experience and data show a significant imbalance in cell capacity with usage, and running below 80% capacity risks permanent damage to the weakest cells.
http://www.unols.org/meetings/1995/199505d...505desap17.html
The main attraction for Sealed Lead Acid (Pb Acid) cells is the low cost of lead. This makes the Pb Acid
cell very inexpensive per watt-hour. Lead is relatively heavy resulting in low volumetric and gravimetric
energy densities (see figure 1.1, Energy Density Comparison). Also, the cycle life of a Pb Acid battery
is directly proportional to the amount of energy removed from the battery during discharge. To obtain an
equivalent cycle life of a NiMH system, only 30% of the Pb Acids capacity can be used.
http://209.85.135.104/search?q=cache:bYkP7...lient=firefox-a