Uve Rick's Battery Page Rescued from Geocities |
What should I look at when deciding which battery to use?
You should be looking for a low Puekert's number. A high Puekert's number means the battery will not provide good range, and will have a large voltage sag. I would not use any battery which has a Puekert's number greater than 1.23.
Why is the Peukert's number important?
Because it suggests the internal resistance of the battery. Suppose a battery has a high 20 hour amp-hr rating, but a high Peukert's number. At the currents needed for EVs, this may not be a good choice. The amp-hr rating at a 1 hour rate or 1/2 hour rate can even be a lot less than a battery with a lower 20 hour amp-hr rating, but a lower Peukert's number.
When deciding on a battery, use the calculator on this page to calculate the the 1 hour or 1/2 hour amp-hr rating. This will give a better indication of the range you can expect.
If I want to have a lot of range, which battery should I use?
Range mainly depends on the weight of the batteries you have in your car, and what percentage that weight is of the total vehicle weight.
If I want to have an inexpensive low maintenance battery, which battery should I use?
I would suggest one of the Concorde batteries. Note that these batteries, though they are AGM type, cannot take the abuse (high currents) that the Optima and Hawker batteries can.
If I want a high performance car, which battery should I use?
I would suggest an Optima or Hawker battery.
If I want an inexpensive moderate range low voltage car, which battery should I use?
I would suggest a T105 or T125-type flooded lead golf car battery.
Are there any precautions which need to be taken for sealed batteries?
A sealed battery must not be overcharged. If you overcharge a sealed battery, you will greatly shorten its life. You can use battery regulators to keep this from happening.
What is cell reversal?
Cell reversal occurs when a cell in the battery has a negative voltage value. This usually happens when a cell is charged in the incorrect direction, as when the cell is completely discharged and current is still being drawn from the battery. The other cells in the battery force current through it, which charges it backwards.
How do you fix a cell reversal?
Put a resistor across the battery over night to completely drain the battery. Then charge the battery with a low current. The battery may be usable, but it will have diminished capacity and life.
How much current can I draw from the battery without damaging the battery?
This depends on the battery and how long you draw the high current. In general, the lower the Peukert's number, the higher the current you can draw from the battery without damaging the battery.
How do I charge my flooded batteries?
Charge batteries at whatever current is available until they reach 2.4 v per cell, +/- .003v per degree C difference from 25 degrees C. The higher the temperature, the lower the voltage. Once the batteries reach 2.4v (temperature corrected), keep the batteries at this voltage until the current falls to 2% of the 20h amp hour rating, expressed in amperes. As an example, 120ah batteries should be charged until the current falls below 2.4 amps.
Equalizing should be carried out about once a week when the batteries are new or very old, and once a month during the normal life of the battery. To equalize, charge the batteries at 2% of their 20h amp hour rating until voltage stops rising. Make sure you keep track of the water level in the battery while equalizing. Equalizing will use water!
How do I charge my AGM batteries?
Battery Charger (Constant Voltage): 13.8 to 15.0 volts, 10 amperes maximum, 8-10 hours approximate.
Float Charge: 13.2 to 13.8 volts, 1 amp maximum current.
Rapid Charge (Constant voltage charger): Maximum voltage 15.6 volts for a 12 volt battery (2.6 volts per cell). No current limit is necessary as long as the internal battery temperature remains below 50 degrees C. Current will taper as the battery becomes charged. When the current falls below 1 amp, the battery will be close to a full state of charge. Recharge time will vary according to temperature and charger characteristics.
Cyclic application or series string applications (CV/CC) only: Constant Voltage with Constant Current finish: 14.7 volts (2.45 volts per cell), temperature < 50 degrees C, no current limits. When current falls below 1 amp, finish with 2 amp constant current for 1 hour.
WARNING: These data are not current. Uve compiled them in the mid to late 1990s. They're reproduced here strictly for historical interest. Please don't try to use them to select new batteries for your EV.
Model |
Volts |
Weight (lbs) |
lngth |
width |
height |
20 hour (ah) |
rsrv cpcty |
cost |
Cycles (80%) |
Trojan SCS225 |
12 |
66 |
|
|
|
135 |
225 |
$85 |
|
DEKA 8G27 |
12 |
62.5 |
|
|
|
|
|
|
|
Trojan T-105 |
6 |
61 |
10.38 |
7.13 |
11.19 |
225 |
447 |
$55 |
733 |
Trojan T-125 |
6 |
66 |
10.38 |
7.13 |
11.19 |
235 |
488 |
$80 |
650 |
Trojan T-145 |
6 |
71 |
10.38 |
7.13 |
11.5 |
244 |
530 |
$95 |
625 |
Trojan T-875 |
8 |
63 |
10.38 |
7.13 |
11.19 |
150 |
295 |
$102 |
|
Trojan T-890 |
8 |
69 |
10.38 |
7.13 |
11.19 |
165 |
340 |
$122 |
|
US 8VGC |
8 |
64.5 |
10.38 |
7.13 |
11.9 |
165 |
318 |
$50 |
|
Trojan 5SHP |
12 |
86 |
13.56 |
6.75 |
11.5 |
165 |
272 |
$220 |
|
Eveready DC27-850 |
12 |
55 |
12.5 |
6.75 |
9.5 |
120 |
180 |
$55 |
|
Douglas 31EV |
12 |
66 |
13 |
6.81 |
10.17 |
135 |
200 |
|
|
Model |
Volts |
Weight (lbs) |
length |
width |
height |
20 hour (ah) |
rsrv cpcty |
cost |
Cycles (80%) |
Optima D750S |
12 |
44.9 |
10.0 |
6.8 |
7.8 |
65 |
125 |
$130 |
220 |
Optima D750U |
12 |
46.1 |
10.0 |
6.8 |
7.8 |
65 |
125 |
$119 |
220 |
Optima Group 31 |
12 |
72 |
13.0 |
6.8 |
9.5 |
100 |
190 |
$140 |
|
Concorde GPC-1234 |
12 |
23 |
7.68 |
5.15 |
7.22 |
33 |
50 |
$58 |
|
Concorde GPC-1248 |
12 |
32 |
9.41 |
5.45 |
9.35 |
48 |
84 |
$85 |
|
Concorde GPC-1260 |
12 |
43 |
10.2 |
6.6 |
9.35 |
60 |
106 |
$102 |
|
Concorde GPC-1272 |
12 |
50 |
11.82 |
6.6 |
9.35 |
72 |
114 |
$114 |
|
Concorde GPC-1280 |
12 |
53 |
10.2 |
6.6 |
9.35 |
80 |
149 |
$118 |
|
Concorde GPC-1285 |
12 |
61 |
|
|
|
85 |
159 |
$138 |
|
Concorde GPC-1295 |
12 |
63 |
11.82 |
6.6 |
9.35 |
95 |
176 |
$152 |
|
Concorde GPC-12105 |
12 |
68 |
12.95 |
6.75 |
9.25 |
105 |
190 |
$166 |
|
Concorde GPC-4D |
12 |
130 |
20.73 |
8.66 |
10.27 |
210 |
380 |
$301 |
|
Concorde GPC-8D |
12 |
158 |
20.62 |
10.95 |
10.17 |
255 |
561 |
$376 |
|
Concorde GPC-6180 |
6 |
55 |
10.4 |
7.11 |
10.91 |
180 |
317 |
$145 |
|
Exide Orbital 34XCD |
12 |
38 |
10.175 |
7 |
7.44 |
50 |
95 |
$98 |
|
Hawker Genesis G12V38Ah10VP |
12 |
32.9 |
7.75 |
6.5 |
6.69 |
46 |
66 |
|
500 |
Hawker Genesis G12V70Ah10EP |
12 |
58 |
13.02 |
6.62 |
7.68 |
72 |
180 |
$200 |
500 |
Hawker Odyssey PC1200 |
12 |
38.2 |
7.87 |
6.66 |
6.8 |
40 |
78 |
|
|
Hawker Odyssey PC1700 |
12 |
60.9 |
13.02 |
6.62 |
6.93 |
65 |
142 |
|
|
Hawker Odyssey PC2150 |
12 |
75 |
13 |
6.8 |
9.4 |
88 |
200 |
|
|
Model |
Volts |
Weight (lbs) |
lngth |
width |
height |
20 hour (ah) |
rsrv cpcty |
cost |
Cycles (80%) |
Ovonic (85ah) |
12 |
35 |
16.1 |
3 |
4 |
112 |
200 |
|
800 |
Ovonic (150ah) |
12 |
49.5 |
15.16 |
4.1 |
8.54 |
185 |
384 |
|
800 |
Model |
Volts |
Weight (lbs) |
lngth |
width |
height |
20 hour (ah) |
rsrv cpcty |
cost |
Cycles (80%) |
Mid term |
12 |
21 |
12.5 |
6.75 |
9.5 |
70 |
140 |
$266 |
600 |
Long term |
12 |
19.5 |
12.5 |
6.75 |
9.5 |
145 |
309 |
$177 |
1000 |
Saft VL Module |
10.65 |
17.6 |
7.5 |
4.9 |
9.5 |
100 |
216 |
$177 |
1500 |