In short
- Conventional: the cheapest option; the electrolyte level needs checking and it has a vent. Must stay upright.
- AGM: sealed, maintenance-free and with low self-discharge. The all-round choice.
- Gel: sealed and durable; many ‘gel’ motorcycle batteries are actually AGM inside.
- Lithium: very light, but loses starting power in cold weather and needs its own charger.
- When replacing a conventional battery with AGM, the voltage regulator must charge at 14.0–14.8 V.
All the motorcycle batteries in this article do the same job: supply the current needed to start the engine and power the motorcycle when the alternator is not charging. What differs is how they hold the electrolyte, how much maintenance they need, how they perform in cold weather and when the bike is parked, and which charger they require.
The four types compared
| Conventional | AGM | Gel | Lithium (LiFePO4) | |
|---|---|---|---|---|
| Electrolyte | Liquid acid | Absorbed in fibreglass separators | Gel | Not lead-based |
| Maintenance | Check the level; top up with distilled water | None; never opened | None | None |
| Vent | Yes | No | No | No |
| Position | Upright only | Upright; factory-activated batteries can be tilted | More tolerant | Check the manufacturer's instructions |
| When parked | Recharge every month | Recharge every 3 months | Low self-discharge | Very low self-discharge |
| Cold-weather performance | Good | Very good | Good | Poorer: starting power drops significantly |
| Charger | Lead-acid, 3 A maximum | Smart motorcycle charger | Smart motorcycle charger | Lithium-specific |
| Price | € | €€ | €€€ | €€€€ |
Conventional flooded battery
This is the traditional battery, with lead plates immersed in liquid acid. Batteries in the YB series (YuMicron) and the 12N series are this type. It is the cheapest option and the only choice for some classic motorcycles, but it needs attention: check the electrolyte level and top up only with distilled water; keep it upright at all times; and route its vent tube away from the chain. It also discharges faster when the motorcycle is parked.
AGM: the all-round choice
In an AGM battery, the electrolyte is absorbed in fibreglass separators, so there is no loose liquid. This means it never needs topping up and won't spill. If it is factory-activated, it can also be fitted at an angle. It discharges more slowly when parked, too. It is ideal for motorcycles left unused for weeks, scooters used for short journeys, quad bikes and personal watercraft (PWC).
There are two families in the Yuasa range:
- YTX and YT: maintenance-free AGM, the most widely used type in motorcycles and scooters.
- YTZ: high-performance AGM, with more starting current in a compact case. Always factory-activated.
If your motorcycle had a conventional battery
An AGM battery can replace a conventional battery with the same case size and polarity, provided the voltage regulator charges at 14.0–14.8 V. Measure the voltage at the terminals with the engine running at 3000–4000 rpm. Some older motorcycles charge below this range; keep using a conventional battery in those cases. If the motorcycle has an electrolyte level sensor, it is specific to conventional batteries and is not used with an AGM.
Gel
Gel batteries have gelled electrolyte. They are sealed, maintenance-free and resistant to deep discharge and repeated charge cycles. There is one thing to bear in mind with motorcycle batteries: many sold as ‘gel’ batteries are actually AGM inside. When choosing a battery, look beyond the name and compare the figures: dimensions, polarity, cold cranking amps and capacity.
Lithium (LiFePO4)
Lithium iron phosphate batteries weigh much less than lead-acid batteries and have very low self-discharge when parked. This makes them popular for racing and motorcycles where every kilo counts. But they work differently:
- Voltage: when healthy and at rest, it should be 13.0 V or higher. Lead-acid voltage charts do not apply to lithium.
- Charging: use a lithium-specific charger. Lead-acid chargers are suitable if they do not exceed 14.4 V and do not have a desulphation mode; this mode uses voltage spikes that can damage the battery. Never exceed 15 V.
- Cold weather: starting power drops significantly at low temperatures, and the battery must not be charged below 0 °C unless its electronics manage this.
- Parasitic drain: an alarm, clock or control unit can drain the battery if the motorcycle is parked for months, and deep discharge will damage it.
When a lithium battery may not be suitable
- For snowmobiles or regular use below freezing.
- For motorcycles with a faulty voltage regulator or one that charges above 15 V.
- For motorcycles with parasitic drain that are parked for months without a battery maintainer.
- For classic motorcycles with a dynamo or poor voltage regulation.
- If you only have a lead-acid charger with a desulphation mode.
So, which one should I choose?
- For almost all motorcycles and scooters: an AGM with the original battery part number. It is maintenance-free, won't spill and has low self-discharge.
- If the original battery is a YTZ: choose another YTZ or its high-performance equivalent. Do not replace it with a YTX with lower starting power.
- Classic motorcycle with a low-output regulator: conventional.
- Racing or saving weight in summer: lithium, with its own charger, and don't leave it for months with parasitic drain.
Whichever technology you choose, the new battery must have the same dimensions and polarity as the original, with equal or higher cold cranking amps. We explain the process step by step in our guide to choosing a motorcycle battery.
Frequently asked questions
Can I fit an AGM battery where a conventional one was?
Yes, if it has the same case size and polarity, and the motorcycle's voltage regulator charges at 14.0–14.8 V. If it charges at a lower voltage, the AGM will not charge fully, so it is better to keep using a conventional battery.
Is a gel battery better than an AGM?
Not necessarily. Both are sealed and maintenance-free, and many motorcycle batteries sold as gel are actually AGM inside. Compare the dimensions, polarity, cold cranking amps and capacity.
Can I charge a lithium battery with my usual charger?
Only if the charger does not exceed 14.4 V and has no desulphation mode. The safest option is a charger with a LiFePO4 lithium profile.
Why won't my lithium battery start the motorcycle in cold weather?
Lithium batteries lose a lot of starting current at low temperatures. Sometimes they need charging to ‘wake up’. For regular use below freezing, an AGM is a better choice.
Satkit battery
OUTDO HCZ12S-MF
12 V, 11.2 Ah battery with 190 A cold cranking amps, replacing the YTZ12S. Factory-activated and charged, ready to fit. Positive terminal on the left.
Where to buyfrom €37.56
Prices incl. VAT checked on 7 October 2026; they may change.
OUTDO UTX12-BS
12 V, 10 Ah battery with 180 A cold cranking amps, a replacement for the YTX12-BS. Factory-activated and charged, ready to fit. Positive terminal on the left.
Where to buyfrom €27.40
Prices incl. VAT checked on 7 October 2026; they may change.
OUTDO YB12AL-BS
12 V, 12 Ah motorcycle battery with 165 A CCA, replacing the YB12AL-A2. Factory-activated and charged; ready to fit. Positive terminal on the right.
Where to buyfrom €35.53
Prices incl. VAT checked on 7 October 2026; they may change.
Sources
- Yuasa, technical manual for motorcycle and recreational vehicle batteries (in English)
- Exide, motorcycle battery range (in English)
- Shorai, LFX lithium battery manual (in English)
- Battery University, charging at high and low temperatures (in English)
