The Yuasa Battery Charging Current Table

The following guide provides instructions for preparing, filling, charging, and maintaining Yuasa batteries. These guidelines, provided by Yuasa Battery, apply to several battery types mentioned in the table below. Additionally, a table of specifications for these batteries, including voltage, capacity, charging current, and density of filling electrolyte, is included for reference.

New Yuasa battery YB12A(L)
Battery TypeVoltage
(V)
Capacity
10H Rate
(AH)
Charging
Current(A)
Volume Of Electrolyte
(liters)
Density of
filling electrolyte
(at 20 c)
6N2/6N2A/B6O620.20.11.26
6N4/6N4A/6N4B/6NAC640.40.21.26
6N5.565.50.550.241.26
6N6660.60.271.26
B386131.30.651.26
B39670.70.31.28
B49680.80.51.26
6N11/6N11A6111.10.41.26
6N126121.20.51.26
B54/6N12A6121.20.451.26
12N51250.50.41.26
12N5.5125.50.550.421.26
12N5.5A125.50.550.481.26
12N7/12N7D1270.70.541.26
12N7B1270.70.51.26
12N91290.90.61.26
12N10121010.721.26
12N1112111.10.81.26
12N12A12121.20.721.26
12N1212121.20.751.26
12N1412141.40.771.26
12N1812181.81.251.26
12N2412242.41.811.26
YB2.5(L)122.50.250.251.28
YB3(L)1230.30.241.28
YB4(L)1240.40.31.28
YB51250.50.361.28
YB71280.80.61.28
YB7C/ YB7B(L)1270.70.51.28
YB9(L)/ YB9A 121290.90.61.28
YB10(L)/ YB10A/SYB10(L)12111.10.71.28
YB10L-BP12121.20.81.28
YB12A-AK121010.751.28
YB12A(L)12121.20.751.28
YB12B12121.20.91.28
YB14(L)/YB14A/SYB14(L)12141.40.871.28
HYB16A12161.611.28
YB16A(L)12161.61.11.28
YB16B(AA1)12161.611.28
YB16(L/C)/ SYB16(L)12191.91.21.28
YB18(L)12181.81.21.28
Y5O-N18(L)/Y5O-N18A122021.41.28
SY5O-N18(L)122021.41.28
Y60-N24(L)/Y60-N24A(L)12282.81.81.28
YHD-1212323.22.11.28
charging current chart

Preparation for Filling a New Yuasa Battery:

  • Take the 6FF sealing tape and remove the vent plugs only right before filling the electrolyte.
  • If your battery has a long-size exhaust tube, cut off its sealed end at about 3 cm (1 inch) from the tip.
  • If your battery has a short-size sealing tube and is supplied with a separate long-size tube, pull off the short one and replace it with the long one.


Filling Electrolyte:

  • Fill the new battery with electrolyte (dilute sulfuric acid) with a density of 1.240 (1.260) for the tropical climate where the average temperature is more than 25°C (77°F), and 1.260 (1.280) for temperate climate.
  • Fill to the UPPER LEVEL as indicated on the Yuasa battery.
  • The electrolyte should be cooled below 30°C (86°F) before filling.
  • Leave the battery standing for half an hour after filling.
  • The electrolyte level may have fallen during the standing period, so refill the acid to the UPPER LEVEL.
  • Figure 1 shows the specific gravity of electrolytes for Yumicron batteries.


Charging:

  • An initial charging is recommended before placing the Yuasa battery in service when time and equipment permit.
  • Charge the battery with a current as described in the Table continuously for 16 to 20 hours.
  • If the electrolyte level is found to fall after charging, fill DISTILLED WATER up to the UPPER LEVEL.
  • After charging, place the vent plugs firmly, wash off the acid spillage with water, and dry the battery.


Installation:

  • Fasten the battery firmly to the vehicle.
  • Be sure not to make a wrong connection between the battery’s positive and negative terminals.
  • Do not fold or crimp the battery’s exhaust tube as it may cause an explosion if the tube is pinched.


Maintenance Service:

  • Check the electrolyte level once a month.
  • If found lower than the middle of the UPPER and LOWER LEVEL, add distilled water to restore the level. Never use acid in this case.
  • Keep the battery always clean and apply grease around the terminals to prevent corrosion.
  • Keep the exhaust tube free of kinks and obstructions.


Recharging:

  • Recharge the weak battery– when you find the lights get dim, the horn weak, and/or when you keep the battery unused for longer than one month.
  • Charge the battery with a current as described in the Table.
  • Charge until the battery starts gassing freely and the specific gravity of electrolyte rises higher than 1.240 in tropical and 1.260 in temperate climates.


Note:

  • Many batteries contain a special chemical called SULFATE STOP that has been added to reduce sulfate crystal deposits that eventually prevent the battery from accepting a charge.
  • SULFATE STOP, whose logo is printed with YUMICRON, is a white powder chemical that may be visible before the battery is activated but dissolves once electrolyte is added.
  • After charging the battery (with SULFATE STOP added), the specific gravity of the electrolyte rises to 1.275-1.260.
  • If the battery contains SULFATE STOP and has not been in use for a long period, extended recharging time is required.
  • A logo identifying that SULFATE STOP has been added is visible on the front case below the acid level markings on your battery.